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COSMOS:

A SKETCH

OP

A PHYSICAL DESCRIPTION OF THE UNIVERSE.

BY

ALEXANDER VON HUMBOLDT.

TRANSLATED FROM THE GERMAN,

BY E. a OTTE.

MatarsB vero rerura vis atque majestas in omnibus momentis fide caret, si qiiia modo partes ejus ac non totara complectatur animo. — Plin., Hist. Nat., lib. viL, c. 1.

IN TWO VOLUMES.

VOL. L

NEW YORK:

HARPER & BROTHERS, PUBLISHERS

329 & 331 PEARL STREET, FRANKLIN SQUARE.

18 56.

TRANSLATOR'S PREFACE.

I CAN not more appropriately introduce the Cosmos than by presenting a brief sketch of the life of its illustrious au- thor.* While the name of Alexander von Humboldt is fa- miliar to every one, few, perhaps, are aware of the peculiar circumstances of his scientific career and of the extent of his labors in almost every department of physical knowledge. He was bom on the 14th of September, 1769, and is, therefore, now in his 80th year. After going through the ordinary course of education at Gottingen, and having made a rapid tour through Holland, England, and France, he became a pu- pil of Werner at the mining school of Freyburg, and in his 21st year published an "Essay on the Basalts of the Rhine." Though he soon became officially connected with the mining corps, he was enabled to continue his excursions in foreign comitries, for, during the six or seven years succeeding the publication of his first essay, he seems to have visited Austria, Switzerland, Italy, and France. His attention to mining did not, however, prevent him from devoting his attention to oth- er scientific pursuits, among which botany and the then re- cent discovery of galvanism may be especially noticed. Bot- any, indeed, we know from his own authority, occupied him almost exclusively for some years ; but even at this time he was practicing the use of those astronomical and physical in- struments which he afterward turned to so singularly excel- lent an account.

The political disturbances of the civilized world at the close

* For the following remarks I am mainly indebted to the articles on the Cosmos in the two leading Quarterly Reviews.

iv translator's preface.

of the last century prevented our author from carrying out various plans of foreign travel which he had contemplated, and detained him an unwilling prisoner in Europe. In the year 1799 he went to Spain, with the hope of entering Africa from Cadiz, but the unexpected patronage which he received at the court of Madrid led to a great alteration in his plans, and decided him to proceed directly to the Spanish posses- sions in America, " and there gratify the longings for foreign adventure, and the scenery of the tropics, which had haunted him from boyhood, but had all along been turned in the dia- metrically opposite direction of Asia." After encountering various risks of capture, he succeeded in reaching America, and from 1799 to 1804 prosecuted there extensive researches in the physical geography of the New World, which have in- delibly stamped his name in the undying records of science.

Excepting an excursion to Naples with Gay-Lussac and Von Buch in 1805 (the year after his return from America), the succeeding twenty years of his life were spent in Paris, and were almost exclusively employed in editing the results of his American journey. In order to bring these results before the world in a manner worthy of their importance, he commenced a series of gigantic publications in almost every branch of science on which he had instituted observations. In 1817, after twelve years of incessant toil, four fifths were completed, and an ordinary copy of the part then in print cost considera- bly more than one hundred pounds sterling. Smce that time the publication has gone on more slowly, and even now, after the lapse of nearly half a century, it remains, and probably ever will remain, incomplete.

In the year 1828, when the greatest portion of his literary labor had been accomplished, he undertook a scientific journey to Siberia, under the special protection of the Russian govern- ment. In this journey — a journey for which he had prepared himself by a course of study unparalleled in the history of travel — he was accompanied by two companions hardly less distinguished than himself, Ehrenberg and Gustav Rose, and

translator's preface. v

the results obtained during their expedition are recorded by our author in his Frag?nents Asiatiques, and in his Asie Ce7itrale, and by Rose in his Reise nach dem Oural. If the Asie Centrale had been his only work, constituting, as it does, an epitome of all the knowledge acquired by himself and by former travelers on the physical geography of Northern and Central Asia, that work alone would have sufficed to form a reputation of the highest order.

I proceed to offer a few remarks on the work of which I now present a new translation to the English pubHc, a work intended by its author " to embrace a summary of physical knowledge, as connected with a delineation of the material universe."

The idea of such a physical description of the universe had, it appears, been present to his mind from a very early epoch. It was a work which he felt he must accomplish, and he de- voted almost a lifetime to the accumulation of materials for it. For almost half a century it had occupied his thoughts ; and at length, in the evening of life, he felt himself rich enough in the accumulation of thought, travel, reading, and experimental research, to reduce into form and reaUty the undefined vision that has so long floated before him. The w;ork, when completed, wiU form three volumes. The first volume comprises a sketch of all that is at present Imown of the physical phenomena of the universe ; the second compre- hends two distinct parts, the first of which treats of the in- citements to the study of nature, afforded in descriptive poet- ry, landscape painting, and the cultivation of exotic plants ; while the second and larger part enters into the consideration of the different epochs in the progress of discovery and of the corresponding stages of advance in human civilization. The third volume, the publication of which, as M. Humboldt him- self informs me in a letter addressed to my learned friend and publisher, Mr. H. G. Bohn, " has been somewhat delayed, owing to the present state of public affairs, will comprise the special and scientific development of the s;reat Picture of Na-

vi translator's preface.

ture." Each of the three parts of the Cosmos is therefore, to a certain extent, distinct in its object, and may be considered complete in itself. We can not better terminate this brief notice than in the words of one of the most eminent philos ophers of our own country, that, " should the conclusion cor- respond (as we doubt not) with these beginnings, a work will have been accomplished every way worthy of the author's fame, and a crowning laurel added to that wreath with which Europe will always delight to surround the name of Alexan der von Humboldt."

In venturing to appear before the English public as the in- terpreter of " the great ivork of our age,^'^ I have been en- couraged by the assistance of many kind literary and scientific friends, and I gladly avail myself of this opportunity of ex- pressing my deep obligations to Mr. Brooke, Dr. Day, Pro fessor Edward Forbes, Mr. Hind, Mr. Glaisher, Dr. Percy, and Mr. Ronalds, for the valuable aid they have afforded me.

It would be scarcely right to conclude these remarks with- out a reference to the translations that have preceded mine. The translation executed by Mrs. Sabine is singularly accu- rate and elegant. The other translation is remarkable for the opposite qualities, and may therefore be passed over in si- lence. The present volumes differ from those of Mrs. Sabine in having all the foreign measures converted into correspond- ing English terms, in being published at considerably less than one third of the price, and in being a translation of the entire work, for I have not conceived myself justified in omit- ting passages, sometimes amounting to pages, simply because they might be deemed slightly obnoxious to our national prej- udices.

* The expression applied to the Cosmos by the learned Bunsen, in his late Report on Ethnology, in the Report of the British Association for 1847, p. 265.

AUTHOR'S PREFACE.

In the late evening of an active life I offer to the German public a work, whose undefined image has floated before my mind for almost half a century. I have frequently looked upon its completion as impracticable, but as often as I have been disposed to relinquish the undertaking, I have again — although perhaps imprudently — resumed the task. This work I now present to my cotemporaries with a diffidence inspired by a just mistrust of my own powers, while I would willingly forget that writings long expected are usually received mth less indulgence.

Although the outward relations of life, and an irresistible impulse toward knowledge of various kinds, have led me to occupy myself for many years — and apparently exclusively — with separate branches of science, as, for instance, with de- scriptive botany, geognosy, chemistry, astronomical determin- ations of position, and terrestrial magnetism, in order that I might the better prepare myself for the extensive travels in which I was desirous of engaging, the actual object of my studies has nevertheless been of a higher character. The principal impulse by which I was directed was the earnest endeavor to comprehend the phenomena of physical objects in their general connection, and to represent nature as one great whole, moved and animated by internal forces. My inter course with highly-gifted men early led me to discover that, without an earnest striving to attain to a knowledge of special branches of study, all attempts to give a grand and general view of the universe would be nothing more than a vain illu- sion. These special departments in the great domain of nat-

v'lii author's preface.

iiral science are, moreover, capable of being reciprocally fruc- tified by means of the appropriative forces by which they are endowed. Descriptive botany, no longer confined to the nar- row circle of the determination of genera and species, leads the observer who traverses distant lands and lofty mountains to the study of the geographical distribution of plants over the earth's surface, according to distance from the equator and ver- tical elevation above the sea. It is further necessary to in- vestigate the laws which regulate the differences of tempera- ture and climate, and the meteorological processes of the at- mosphere, before we can hope to explain the involved causes of vegetable distribution ; and it is thus that the observer who earnestly pursues the path of knowledge is led from one class of phenomena to another, by means of the mutual dependence and connection existing between them.

I have enjoyed an advantage which few scientific travelers have shared to an equal extent, viz., that of having seen not only littoral districts, such as are alone visited by the majority of those who take part in voyages of circumnavigation, but also those portions of the interior of two vast continents which present the most striking contrasts manifested in the Alpine tropical landscapes of South America, and the dreary wastes of the steppes in Northern Asia. Travels, undertaken in dis- tricts such as these, could not fail to encourage the natural tendency of my mind toward a generalization of views, and to encourage me to attempt, m a special work, to treat of the knowledge which we at present possess, regarding the sidereal and terrestrial phenomena of the Cosmos in their empirical relations. The hitherto undefined idea of a physical geog- raphy has thus, by an extended and perhaps too boldly imag- ined a plan, been comprehended under the idea of a physical description of the universe, embracing all created things in the regions of space and in the earth.

The very abundance of the materials which are presented to the mind for arrangement and definition, necessarily impart uo inconsiderable difficulties in the choice of the form utidev

AUTHOR S PREFACE. * IX

which such a work must be presented, if it would aspire to the honor of being regarded as a Hterary composition. De- scriptions of nature ought not to be deficient in a tone of life- like truthfulness, while the mere enumeration of a series of general results is productive of a no less wearying impression than the elaborate accumulation of the individual data of ob- servation, i scarcely venture to hope that I have succeeded in satisfying these various requirements of composition, or that I have myself avoided the shoals and breakers which I have known how to indicate to others. My faint hope of success rests upon the special indulgence which the German public have hestowed upon a small work bearing the title of Ansich- ten der Natur, which I pubhshed soon after my return from Mexico. This work treats, under general points of view, of separate branches of physical geography (such as the forms of vegetation, g;rassy plains, and deserts). The efiect produced by this small volimie has doubtlessly been more powerfully manifested in the influence it has exercised on the sensitive minds of the young, whose imaginative faculties are so strong- ly manifested, than by means of any thing which it could it- self impart. In the work on the Cosmos on which I am now engaged, I have endeavored to show, as in that entitled An- sichten der Natur, that a certain degree of scientific com- pleteness in the treatment of individual facts is not wholly incompatible with a picturesque animation of style.

Since public lectures seemed to me to present an easy and efficient means of testing the more or less successful manner of connecting together the detached branches of any one sci- ence, I undertook, for many months consecutively, first in the French language, at Paris, and afterward in my own native German, at Berhn (almost simultaneously at two different places of assembly), to deUver a course of lectures on the phys- ical description of the universe, according to my conception of the science. My lectures were given extemporaneously, both in French and German, and without the aid of written notes, nor have I, in any way, made use, in the present work,

author's preface.

of those portioiis of my discourses which have been preserved by the industry of certain attentive auditors. V/ith the ex- ception of the first forty pages, the whole of the present work was written, for the first time, in the years 1843 and 1844.

A character of unity, freshness, and animation must, I think, be derived from an association with some definite epoch, where the object of the writer is to delineate the pres- ent condition of knowledge and opinions. Since the addi- tions constantly made to the latter give rise to fundamental changes in pre-existing views, my lectures and the Cosmos have nothing in common beyond the succession in which the various facts are treated. The first portion of my work con tains introductory considerations regarding the diversity in the degrees of enjoyment to be derived from nature, and the knowledge of the laws by which the universe is governed ; it also considers the limitation and scientific mode of treatinjr a physical description of the universe, and gives a general pic- ture of nature which contains a view of all the phenomena comprised in the Cosmos.

This general picture of nature, which embraces within its wide scope the remotest nebulous spots, and the revolving double stars in the regions of space, no less than the telluric phenomena included under the department of the geography of organic forms (such as plants, animals, and races of men), comprises all that I deem most specially important vdth re- gard to the connection existing between generalities and spe- cialities, while it moreover exemplifies, by the form and style of the composition, the mode of treatment pursued in the se- lection of the results obtained from experimental knowledge. The two succeeding volumes will contain a consideration of the particular means of incitement toward the study of na- ture (consisting in animated delineations, landscape painting, and the arrangement and cultivation of exotic vegetable forms), of the history of the contemplation of the universe, or the gradual development of the reciprocal action of natural forces constituting one natural whole ; and, lastly, of the spe-

AUTHOR ^^ PREFACE-. XI

cial branches of the several departments of scienet, whose mutual connection is indicated in the beginning of the work. Wherever it has been possible to do so, I have adduced the au- thorities from whence I derived my facts, with a view of afibrd- ing testimony both to the accuracy of my statements and to the value of the observations to which reference was made. In those instances where I have quoted from my own writings (the facts contained in which being, from their very nature, scat- tered through different portions of my works), I have always referred to the original editions, owing to the importance of accuracy with regard to numerical relations, and to my own distrust of the care and correctness of translators. In the few cases where I have extracted short passages from the works of my friends, I have indicated them by marks of quotation ; and, in imitation of the practice of the ancients, I have inva- riably preferred the repetition of the same words to any arbi- ti'ary substitution of my own paraphrases. The much-con- tested question of priority of claim to a first discovery, which it is so dangerous to treat of in a work of this uncontroversial kind, has rarely been touched upon. Where I have occasion- ally referred to classical antiquity, and to that happy period of transition which has rendered the sixteenth and seventeenth centuries so celebrated, owing to the great geographical dis- coveries by which the age was characterized, I have been sim- ply led to adopt this mode of treatment, from the desire we experience from time to time, when considering the general views of nature, to escape from the circle of more strictly dog- matical modern opinions, and enter the free and fanciful do- main of earlier presentiments.

It has frequently been regarded as a subject of discouraging consideration, that while purely literary products of intellect ual activity are rooted in the depths of feeling, and interwoven with the creative force of imagination, all works treating of empirical knowledge, and of the connection of natural phe- nomena and physical laws, are subject to the most marked modifications of form in the lapse of short periods of time, both

xii author's preface.

by the improvement in the instruments used, and by the con- sequent expansion of the field of view opened to rational ob- servation, and that those scientific works which have, to use a common expression, become mitiquated by the acquisition of new funds of knowledge, are thus continually being con- signed to oblivion as unreadable. However discouraging such a prospect must be, no one who is animated by a genuine love of nature, and by a sense of the dignity attached to its study, can view with regret any thing which promises future addi- tions and a greater degree of perfection to general knowledge. Many important branches of knowledge have been based upon a solid foundation which will not easily be shaken, both as re- gards the phenomena in the regions of space and on the earth ; while there are other portions of science in which general views will undoubtedly take the place of merely special ; where new forces will be discovered and new substances will be made known, and where those which are now considered as simple will be decomposed. I would, therefore, venture to hope that an attempt to delineate nature in all its vivid ani- mation and exalted grandeur, and to trace the stahle amid the vacillating, ever-recurring alternation of physical metamorph- oses, will not be wholly disregarded even at a future age. PoUdam, Nov., 1844.

CONTENTS OF VOL. I.

Page

The Translator's Preface iii

The Author's Preface vii

Summary xv

INTRODUCTION.

The Results of the Study of Physical Phenomena 23

The different Epochs of the Contemplation of the external World. 24 The different Degrees of Enjoyment presented by the Contempla- tion of Nature 25

Instances of this Species of Enjoyment 26

Means by which it is induced 26

The Elevations and climatic Relations of many of the most cele- brated Mountains in the World, considered with Reference to the

Effect produced on the Mind of the Observer 27-33

The Impressions awakened by the Aspect of tropical Regions ... 34 The more accurate Knowledge of the Physical Forces of the Uni- verse, acquired by the Inhabitants of a small Section of the tem- perate Zone 36

The earliest Dawn of the Science of the Cosmos 36

The Difficulties that opposed the Progress of Inquiry 37

Consideration of the Effect produced on the Mind by the Observa- tion of Nature, and the Fear entertained by some of its injurious

Influence 40

Illustrations of the Manner in which many recent Discoveries have tended to Remove the groundless Fears entertained regarding

the Agency of certain Natural Phenomena 43

The Amount of Scientific Knowledge required to enter on the

Consideration of Physical Phenomena 47

The Object held in View by the present Work 49

The Nature of the Study of the Cosmos 50

The special Requirements of the present Age 53

Limits and Method of Exposition of the Physical Description of the

Universe 56

Considerations on the terms Physiology and Physics 58

Physical Geography 59

Celestial Phenomena 63

The Natural Philosophy of the Ancients directed more to Celestial

than to Terrestrial Phenomena 65

The able Treatises of Varenius and Carl Ritter 66, 61

Signification of the Word Cosmos .-. . 68—70

The Domain embraced by Cosmography 71

Empiricism and Experiments 74

The Process of Reason and Induction 77

XIV CONTENTS.

GENERAL REVIEW OF NATIJRAL PHENOMENA.

Connection betweei^ the Material and the Ideal World 80

Delineation of Nature 82

Celestial Phenomena 83

Sidereal Systems 89

Planetary Systems 90

Comets 99

Aerolites Ill

Zodiacal Light 137

Translatory Motion of the Solar System 145

The Milky Way 150

Starless Open'ngs 152

Terrestrial Phenomena 154

Geographical Distribution 161

Fio-ure of the Earth 163

Density of the Earth 169

Internal Heat of the Earth 172

Mean Temperature of the Earth 175

Terrestrial Magnetism 177

Magnetism 183

Aurora Borealis 193

Geoo-nostic Phenomena 202

Earthquakes 204

Gaseous Emanations , 217

Hot Springs 221

Salses 224

Volcanoes 227

Rocks 247

PalfEontology 270

Geognostic Periods 286

Physical Geography 287

Meteorology " 311

Atmospheric Pressure 315

Climatology 317

The Snow-line 329

Hygrometry 332

Atmospheric Electricity 335

Organic Life 339

Motion in Plants 341

Universality of Animal Life 342

Geography of Plants and Animals 346

Floras of different Countries 350

Man 352

Races 353

Language 357

Conclusion of the Subject < 359

SUMMARY.

Translator's Preface. Author's Preface.

«

Vol. I.

GENERAL SUMMARY OF THE CONTENTS.

Introduction. — Rejlections on the different Degrees of Enjoyment pre' sented to us by the Aspect of Nature and the scientific Exposition of the Laws of the Universe Page 23-78

Insight mto the connection of phenomena as the aim of all natural investigation. Nature presents itself to meditative contemplation as a jnity in diversity. Differences in the grades of enjoyment yielded by nature. Effect of contact with free nature ; enjoyment derived from nature independently of a knowledge of the action of natural forces, or of the effect produced by the individual character of a locality. Effect of the physiognomy and configuration of the surface, or of the character of vegetation. Reminiscences of the woody valleys of the Cordilleras and of the Peak of Teneriffe. Advantages of the mountainous region near the equator, where the multiplicity of natural impressions attains its maximum within the most circumscribed limits, and where it is permitted to man simultaneously to behold all the stars of the firma- ment and all the forms of vegetation — p. 23-33.

Tendency toward the investigation of the causes of physical phenom ena. Erroneous views of the character of natural forces arising from an imperfect mode of observation or of induction. The crude accu- mulation of physical dogmas transmitted from one century to another. Their diffusion among the higher classes. Scientific physics are asso- ciated with another and a deep-rooted system of untried and misunder- stood experimental positions. Investigation of natural laws. Appre- hension that nature may lose a portion of its secret charm by an inquiry into the internal character of its forces, and that the enjoyment of na ture must necessarily be weakened by a study of its domain. Advant ages of general views which impart an exalted and solemn character to natural science. The possibility of separating generalities from specialities. Examples drawn from astronomy, recent optical discov eries, physical geognosy, and the geography of plants. Practicabil ity of the study of physical cosmography — p. 33-54. Misunderstood popular knowledge, confounding cosmography with a mere encyclope- dic enumeration of natural sciences. Necessity for a simultaneous re- gard for all branches of natural science. Influence of this study on national prosperity and the welfare of nations ; its more earnest and characteristic aim is an inner one, arising from exalted mental activity. Mode of treatment with regard to the object and presentation ; recip- rocal connection existing between thought and speech — p. 54-5C

The notes to p. 28-33. Comparative hypsometrical data of the eleva- tions of the Dhawalagiri, Jawahir, Chimborazo, iEtna (according to the measureraeutof Sir John Herschel), the Swiss Alps, &c. — p. 28. Rarity

XVI SUMMARY OF THE CONTENTS.

of palms and ferns in the Himalaya Mountains — p. 29. European vz- etable forms in the Indian Mountains — p. 30. Northern and southern limits of perpetual snow on the Himalaya ; influence of the elevated plateau of Thibet — p. 30-33. Fishes of an earlier world — p. 46.

Limits and Method of Exposition of the ^Physical Description of the

Universe Page 56-78

Subjects embraced by the study of the Cosmos or of physical cosmog raphy. Separation of other kindred studies — p. 56-62. The urano- logical portion of the Cosmos is more simple than the telluric ; the im- possibility of ascertaining the diversity of matter simplifies the study of the mechanism of the heavens. Origin of the word Cosmos, its sig- nification of adornment and order of the universe. The existijig can not be absolutely separated in our contemplation of nature from the future. Histoiy of the world and description of the world — p. 62-73. Attempts to embrace the multiplicity of the phenomena of the Cos- mos in the unity of thought and under the form of a purely rational combination. Natural philosophy, which preceded all exact observa- tion in antiquity, is a natural, but not unfrequently ill-directed, eftbrt of reason. Two forms of abstraction rule the whole mass of knowl- edge, viz.: the quantitative, relative deteraiinations according to num- ber and magnitude, and qualitative, material characters. Means of submitting phenomena to calculation. Atoms, mechanical methods of construction. Figurative representatiojus ; mythical conception of im- ponderable matters, and the peculiar vital forces in every organism. That which is attained by obsex-vation and experiment (calling forth phenomena) leads, by analogy and induction, to a knowledge of empir- ical laws; their gradual simplification and generalization. Arrange- ment of the facts discovered in accordance with leading ideas. The treasure of empirical contemplation, collected through ages, is in no dan- ger of experiencing any hostile agency from philosophy — p. 73-78.

[In the notes appended to p. 66-70 are considerations of the general and comparative geography of Varenius. Philological investigation into the meaning of the words Koafiog and mundus.']

Delineation of Nature. General Review of Natural Phenomena

p. 79-359

Introduction — p. 79-83. A descriptive delineation of the world embraces the whole universe {to tt&v) in the celestial and terrestrial spheres. Form and course of the representation. It begins with the depths of space, of which we know little beyond the existence of laws of gravitation, and with the region of the remotest nebulous spots and double stars, and then, gradually descending through the starry stratum to w^hich our solar system belongs, it contemplates this terres- trial spheroid, surrounded by air and water, and, finally, proceeds to the consideration of the form of our planet, its temperature and mag- netic tension, and the fullness of organic vitality which is unfolded on its surface under the action of light. Partial insight into the relative dependence existing among all phenomena. Amid all the mobile and unstable elements in space, mean numerical vahces are the ultimate aim of investigation, being the expression of the physical laws, or forces of the Cosmos. The delineation of the universe does not begin with the eai'th, from which a merely subjective point of view might have led ua to start, but rather with the objects comprised in the regions of space. Distribution of matter, which is partially conglomerated into rotating

SUMMARY OF THE CONTENTS. XVil

nnd circling heavenly bodies of veiy different density and magnitude, and partly scattered as self-luminous vapor. Review of the separate portions of the picture of nature, for the purpose of explaining the re- ciprocal connection of all phenomena.

I. Celestial Portion of the Cosmos Page 83-154

II. Terrestrial Portion, of the Cosmos p. 154-359

a. Form of the earth, its mean density, quantity of heat, electro-mag- netic activity, process of light — p. 154-202.

b. Vital activity of the earth toward its external surface. Reaction of the interior of a planet on its crust and surface. Subterranean noise without waves of concussion. Earthquakes dynamic phenomena — p. 202-217.

c. Mateiial pi'oducts which frequently accompany earthquakes. Gas- eous and aqueous springs. Salses and mud volcanoes Upheavals of the soil by elastic forces — p. 217-228.

d. Fire-emitting mountains. Craters of elevation. Distribution of volcanoes on the earth — p. 228-247.

e. Volcanic foi'ces form new kinds of rock, and metamorphose those already existing. Geognostical classification of rocks into four groups. Phenomena of contact. Fossiliferous strata ; their vertical arrangement. The faunas and floras of an earlier world. Distribution of masses of rock— p. 247-284.

/. Geognostical epochs, which are indicated by the mineralogical dif- ference of rocks, have determined the distnbution of solids and fluids into continents and seas. Individual configuration of solids into hori- zontal expansion and vertical elevation. Relations of area. Articula- tion. Probability of the continued elevation of the earth's crust in ridges— p. 284-301.

0-. Liquid and aenform envelopes of the solid surface of our planet. Distribution of heat in both. The sea. The tides. CuiTents and their effects— p. 301-311.

h. The atmosphere. Its chemical composition. Fluctuations in its density. Law of the direction of the winds. Mean temperature. Enu- meration of the causes which tend to raise and lower the temperature. Continental and insular climates. East and west coasts. Cause of the curvature of the isothermal lines. Limits of perpetual snow. Quantity of vapor. Electricity in the atmosphere. Forms of the clouds — p. 311-339.

i. Separation of inorganic terrestrial life from the geogi-aphy of vital organisms; the geography of vegetables and animals. Physical grada- tions of the human race — p. 339-359.

Special Analysis of the Delineation of Nature, including References to the

Subjects treated of in the Notes.

[. Celestial Portion of the Cosmos p. 83-154

The universe and all that it compnses — multiform nebulous spots, planetary vapor, and nebulous stai-s. The pictui'esque charm of a southern sky — note, p. 85. Conjectures on the position in space of the world. Our stellar masses. A cosmical island. Gauging stars. Double stars revolving round a common center. Distance of the star 6 1 Cygui — p. 88 and note. Our solar system more complicated than was conjectured at the close of the last century. Primary planets with Nep- tune, Astrea, Hebe, Iris, and Flora, now constitute 16 ; secondary plan- ets 18 ; myriads of comets of which many of the inner ones are inclosed

XVm SUMMARY OF THE CONTENTS.

in the orbits of the planets ; a rotating ring (the zodiacal light) and me- teoric stones, probably to be regarded as small cosmical bodies. The telescopic planets, Vesta, Junoj Ceres, Pallas, Astrea, Hebe, Iris, and Flora, with their frequently intersecting, strongly inclined, and more eccentric orbits, constitute a central group of separation between the inner planetary group (Mercury, Venus, the Earth, and Mars) and the outer group (Jupiter, Saturn, Uranus, and Neptune). Contrasts of these planetary groups. Relations of distance from one central body. Dif- fei'ences of absolute magnitude, density, period of revolution, eccentric- ity, and inclination of the orbits. The so-called law of the distances of the planets from their central sun. The planets which have the largest number of moons — p. 96 and note. Relations in space, both absolute and relative, of the secondary planets. Largest and smallest of the moons. Greatest appi'oximation to a primary planet. Retrogressive movement of the moons of Uranus. Libration of the Earth's satellite — p. 98 and note. Comets ; the nucleus and tail ; various forms and di- rections of the emanations in conoidal envelopes, with more or less dense walls. Several tails inclined toward the sun ; change of form of the tail; its conjectured rotation. Nature of light. Occultations of the fixed stars by the nuclei of comets. Eccentricity of their orbits and periods of revolution. Greatest distance and greatest approximation of comets. Passage through the system of Jupiter's satellites. Comets of short periods of revolution, more correctly termed inner comets (Encke, Biela, Faye) — p. 107 and note. Revolving a6rolites (meteoric stones, fire-balls, falling stars). Their planetary velocity, magnitude, form, observed height. Periodic return in streams; the November stream and the stream of St. Lawrence. Chemical composition of me- teoric asteroids — p. 130 and notes. Ring of zodiacal light. Limita- tion of the present solar atmosphere — p. 141 and note. Translatory motion of the whole solar system — p. 145-149 and note. The exist- ence of the law of gravitation beyond our solar system. The milky way of stars and its conjectured breaking up. Milky way of nebulous spots, at right angles with that of the stars. Periods of revolutions of bi-colored double stars. Canopy of stars; openings in the stellar stra- tum. Events in the universe ; the apparition of new stars. Propaga- tion of light, the aspect of the stai'ry vault of the heavens conveys to the mind an idea of inequality of time — p. 149-154 and notes.

II. Terrestrial Portion of the Cosmos Page 154-359

a. Figure of the earth. Density, quantity of heat, electro-magnetic tension, and terrestrial light — p. 154-202 and note. Knowledge of the compression and curvature of the earth's surface acquired by meas- urements of degrees, pendulum oscillations, and certain inequalities in the moon's orbit. Mean density of the earth. The earth's crust, and the depth to which we are able to penetrate — p. 159, 160, note. Three- fold movement of the heat of the earth ; its thermic condition. Law of the increase of heat with the increase of depth — p. 160, 161 and note. Magnetism electricity in motion. Periodical variation of terrestrial magnetism. Disturbance of the regular course of the magnetic needle. Magnetic stoiins ; extension of their action. Manifestations of magnet- ic force on the earth's surface presented under three classes of phe- nomena, namely, lines of equal force (isodynamic), equal inclination (isoclinic), and equal deviation (isogenic). Position of the magnetic pole. Its probable connection with the poles of cold. Change of all the magnetic phenomena of the earth. Erection of magnetic observa-

SUMMARY OF THE CONTENTS. XIX

toi-ies since 1828 ; a far-extending net-work of magnetic stations — p. 190 and note. Development of light at the magnetic poles; terrestrial light as a consequence of the electro-magnetic activity of our planet. Elevation of polar light. Whether magnetic storms are accompanied by noise. Connection of polar light (an electro-magnetic development of light) with the formation of cirrus clouds. Other examples of the generation of terrestrial light — p. 202 and note.

b. The vital activity of a planet manifested from within outward, the principal source of geognostic phenomena. Connection between mere- ly dynamic concussions or the upheaval of whole portions of the earth's crust, accompanied by the eflfusion of matter, and the generation of gaseous and liquid fluids, of hot mud and fused earths, which solidify into rocks. Volcanic action, in the most general conception of the idea, is the reaction of the interior of a planet on its outer surface. Earth- quakes. Extent of the circles of commotion and their gradual increase. Whether there exists any connection between the changes in terres- trial magnetism and the processes of the atmosphere. Noises, subter- ranean thunder without any perceptible concussion. The rocks which modify the propagation of the waves of concussion. Upheavals ; erup- tion of water, hot steam, mud mofettes, smoke, and flame during au earthquake — p. 202-218 and notes.

c. Closer consideration of material products as a consequence of internal planetary activity. There rise from the depths of the earth, through fissures and cones of eruption, various gases, liquid fluids (pure or acidulated), mud, and molten earths. Volcanoes are a species of intermittent spring. Temperature of thermal springs; their constancy and change. Depth of the foci — p. 219-224 and notes. Salses, mud volcanoes. While fire-emitting mountains, being sources of molten earths, produce volcanic rocks, spring water forms, by precipitation, strata of limestone. Continued generation of sedimentary rocks — p 228 and note.

d. Diversity of volcanic elevations. Dome-like closed trachytic mountains. Actual volcanoes which are formed from craters of eleva- tion or among the detritus of their original structure. Permanent con- nection of the interior of our earth with the atmosphere. Relation to certain rocks. Influence of the relations of height on the frequency of the eruptions. Height of the cone of cinders. Characteristics of those volcanoes v^'hich rise above the snow-line. Columns of ashes and fire. Volcanic storm during the eruption. Mineral composition of lavas — p. 236 and notes. Distribution of volcanoes on the earth's surface ; central and linear volcanoes ; insular and littoral volcanoes. Distance of volcanoes from the sea-coast. Extinction of volcanic forces — p. 246 and notes.

e. Relation of volcanoes to the character of rocks. Volcanic forces form new rocks, and metamorphose the more ancient ones. The study of these relations leads, by a double course, to the mineral portion of geognosy (the study of the textures and of the position of the earth's strata), and to the configuration of continents and insular groups ele- vated above the level of the sea (the study of the geographical form and outlines of the different pai*ts of the earth). Classification of rocks according to the scale of the phenomena of structure and metamorpho- sis, which are still passing before our eyes. Rocks of eruption, sedi- mentary rocks, changed (metamorphosed) rocks, conglomerates — com- pound rocks are definite associations of oryctognostically simple fossils There are four phases in the formative condition: rocks of eruption.

XX SUMIMARY OF THE CONTENTS.

endogenous (granite, sienite, porphyry, greenstone, hypersthene, rockj eupliotide, melapbyre, basalt, and phonolithe); sedimentary rocks (si- lurian schist, coal measures, limestone, travertino, infusorial deposit) ; metamorphosed rock, which contains also, together with the detritus of the rocks of eruption and sedimentary rocks, the remains of gneiss, mica schist, and more ancient metamorphic masses. Aggregate and sandstone formations. The phenomenon of contact explained by the artificial imitation of minerals. Effects of pressure and the various ra- pidity of cooling. Origin of granular or saccharoidal marble, silicifica- tion of schist into ribbon jasper. Metamorphosis of calcareous marl into micaceous schist through granite. Conversion of dolomite and granite into argillaceous schist, by contact with basaltic and doleritie rocks. Filling up of the veins from below. Processes of cementation in agglomerate structures. Friction conglomerates — p. 269 and note. Relative age of rocks, chronometry of the earth's crust. Fossiliferous strata. Relative age of organisms. Simplicity of the first \atal forms. Dependence of physiological gradations on the age of the formations. Geognostic horizon, whose careful investigation may yield certain data regarding the identity or the relative age of formations, the periodic recurrence of certain strata, their parallelism, or their total suppression. Types of the sedimentary structures considered in their most simple and general characters ; silurian and devonian formations (formerly known as rocks of transition); the lower trias (mountain limestone, coal measures, together with todtliegende and zechstein) ; the upper ti'ias (bunter sandstone, muschelkalk, and keuper) ; Jura limestone (lias and oolite) ; freestone, lower and upper chalk, as the last of the flotz strata, which begin with mountain limestone ; tertiaiy formations in three divisions, which are designated by granular limestone, lignite, and south Apennine gravel — p. 269-278.

The faunas and floras of an earlier world, and their relations to exist- ing organisms. Colossal bones of antediluvian mammalia in the upper alluvium. Vegetation of an earlier world ; monuments of the history of its vegetation. The points at which certain vegetable groups attain their maximum; cycadeae in the keuper and lias, and coniferae in the bunter sandstone. Lignite and coal measures (amber-tree). Deposition of large masses of rock ; doubts regarding their origin — p. 285 and note

/. The knowledge of geognostic epochs — of the upheaval of mount- ain chains and elevated plateaux, by which lands are both formed and destroyed, leads, by an internal causal connection, to the distribution into solids and fluids, and to the peculiarities in the natural configura- tion of the earth's surface. Existing areal relations of the solid to the fluid differ considerably from those presented by the maps of the phys- ical portion of a more ancient geography. Importance of the eruption of quartzose porphyry with reference to the then existing configuration of continental masses. Individual conformation in horizontal exten- sion (relations of articulation) and in vertical elevation (hypsometrical views). Influence of the relations of the area of land and sea on the temperature, direction of the winds, abundance or scarcity of organic products, and on all meteorological processes collectively. Direction of the major axes of continental masses. Articulation and pyramidal termination toward the south. Series of peninsulas. Valley-like form- ation of the Atlantic Ocean. Forms which frequently recur — p. 285- 293 and notes. Ramifications and systems of mountain chains, and tho means of determining their relative ages. Attempts to determine the *enter of gravity of the volume of the lauds upheaved above the level

SUMMARY OF THE CONTENTS. XXI

of the sea. The elevation of continents is still progressing slowly, and is being compensated for at some definite points by a perceptible sink- ing. All geognostic phenomena indicate a periodical alternation of activity in the interior of our planet. Probability of new^ elevations of ridges — p. 293-301 and notes.

g. The solid surface of the earth has two envelopes, one liquid, and tlie other aeriform. Contrasts and analogies which these envelopes— tlie sea and the atmosphere — present in their conditions of aggrega^ tion and electricity, and in their relations of currents and temperature. Depths of the ocean and of the atmosphei-e, the shoals of which consti tute our highlands and mountain chains. The degree of heat at the surface of the sea in different latitudes and in the lower strata. Tend- ency of the sea to maintain the temperature of the surface in the strata nearest to the atmosphere, in consequence of the mobility of its j)arti- cles and the alteration in its density. Maximum of the density of salt water. Position of the zones of the hottest water, and of those having the greatest saline contents. Thermic influence of the lower polar cur- rent and the counter currents in the straits of the sea — p. 302-304 and notes. General level of the sea, and permanent local disturbances of equilibrium ; the periodic disturbances manifested as tides. Oceanic currents; the equatorial or rotation current, the Atlantic warm Gulf Stream, and the further impulse which it receives; the cold Peruvian stream in the eastern portion of the Pacific Ocean of the southern zone. Temperature of shoals. The universal diffusion of life in the ocean. Influence of the small submarine sylvan region at the bottom of beds of rooted algse, or on far-extending floating layers of fucus — p. 302-311 and notes.

k. The gaseous envelope of our planet, the atmosphere. Chemical composition of the atmosphere, its transparency, its polarization, pres sure, temperature, humidity, and electric tension. Relation of oxygen to nitrogen ; amount of carbonic acid; carbureted hydrogen; ammo- niacal vapors. Miasmata. Regular (horaiy) changes in the pressure of the atmosphere. Mean barometrical height at the level of the sea in different zones of the earth. Isobarometx'ical curves. Barometrical windroses. Law of rotation of the winds, and its importance with ref- erence to the knowledge of many meteorological processes. Land and sea winds, trade winds and monsoons — p. 311-317. Climatic distribu- tion of heat in the atmosphere, as the effect of the relative position of transparent and opaque masses (fluid and solid superficial area), and of the hypsometrical configuration of continents. Curvature of the iso- thermal lines in a horizontal and vertical direction, on the earth's sur- face and in the superimposed strata of air. Convexity and concavity of the isothermal lines. Mean heat of the year, seasons, months, and days. Enumeration of the causes which produce disturbances in the form of the isothermal lines, i. e., their deviation from the position of the geographical parallels. Isochimenal and isotheral lines are the lines of equal winter and summer heat. Causes which raise or lower the tem- perature. Radiation of the earth's surface, according to its inclination, color, density, dryness, and chemical composition. The form of the cloud which announces what is passing in the upper strata of the atmos- phere is the image of the strongly radiating ground projected on a hot summer sky. Contrast between an insular or littoral climate, such as is experienced by all deeply-articulated continents, and the climate of the interior of large tracts of land. East and west coasts. Ditlerence between the southern and northern hemispheres. Thennal scales of

XXll SUMMARY OF THE CONTENTS.

cultivated plants, going down from the vanilla, cacoa, and musacese, to citrons and olives, and to vines yielding potable wines. The influence which these scales exercise on the geographical distribution of culti- vated plants. The favorable ripening and the immaturity of fruits are essentially influenced by the difference in the action of direct or scat- tered light in a clear sky or in one overcast with mist. General sum- mary of the causes which yield a more genial climate to the greater portion of Europe considered as the western peninsula of Asia — ^p. 326. Determination of the changes in the mean annual and summer temper- ature, which correspond to one degree of geographical latitude. Equal- ity of the mean temperature of a mountain station, and of the polar dis- tance of any point lying at the level of the sea. Decrease of tempera- ture with the decrease in elevation. Limits of perpetual snow, and the fluctuations in these limits. Causes of disturbance in the regularity of the phenomenon. Northern and southern chains of the Himalaya; hab- itability of the elevated plateaux of Thibet — p. 33 1 . Quantity of moist- ure in the atmosphere, according to the hours of the day, the seasons of the year, degrees of latitude, and elevation. Greatest dryness of the atmosphere observed in Northern Asia, between the river disti-icts of the Irtysch and the Obi. Dew, a consequence of radiation. Quantity of rain — p. 335. Electricity of the atmosphere, and disturbance of the electric tension. Geographical distribution of storms. Predetermina tion of atmospheric changes. The most important climatic disturbances can not be traced, at the place of observation, to any local cause, but are rather the consequence of some occurrence by which the equilibrium in the atmospheric currents has been destroyed at some considerable distance — p. 335-339.

i. Physical geography is not limited to elementary inorganic terres- trial life, but, elevated to a higher point of view, it embraces the sphere of organic life, and the numerous gradations of its typical development. Animal and vegetable life. General diffusion of life in the sea and on the land; microscopic vital forms discovered in the polar ice no less than in the depths of the ocean within the tropics. Extension imparted to the horizon of life by Ehrenberg's discoveries. Estimation of the mass (volume) of animal and vegetable organisms — p. 339-346. Geog- raphy of plants and animals. Migrations of organisms in the ovum, or by means of organs capable of spontaneous motion. Spheres of distri- bution depending on climatic relations. Regions of vegetation, and classification of the genera of animals. Isolated and social living plants and animals. The character of floras and faunas is not deteimined so much by the predominance of separate families, in certain parallels of latitude, as by the highly complicated relations of the association of many families, and the relative numerical value of their species. The forms of natural families which increase or decrease from the equator to the poles. Investigations into the numerical relation existing in different districts of the earth between each one of the large families to the whole mass of phanerogamia — p. 346-351. The human race considered according to its physical gradations, and the geographical distribution of its simultaneously occurring types. Races and varieties. All races of men are forms of one single species. Unity of the human race. Languages considered as the intellectual creations of mankind, or as portions of the history of mental activity, manifest a character of nation- ality, although certain historical occurrences have been the means of diffusing idioms of the same family of languages among nations of wholb^ different descent — p. 351-359.

INTRODUCTION.

REFLECTIONS ON THE DIFFERENT DEGREES OF ENJOYMENT PRE- SENTED TO US BY THE ASPECT OF NATURE AND THE STUDY OF HER LAWS.

In attempting, after a long absence from my native coun- try, to develop the physical phenomena of the globe, and the simultaneous action of the forces that pervade the regions of space, I experience a two-fold cause of anxiety. The subject before me is so inexhaustible and so varied, that I fear either to fall into the superficiality of the encyclopedist, or to weary the mind of my reader by aphorisms consisting of mere gener- alities clothed in dry and dogmatical forms. Undue concise- ness often checks the flow of expression, while diffuseness is alike detrimental to a clear and precise exposition of our ideas. Nature is a free domain, and the profound conceptions and enjoyments she awakens within us can only be vividly deline- ated by thought clothed in exalted forms of speech, worthy of bearing witness to the majesty and greatness of the creation.

In considering the study of physical phenomena, not mere- ly in its bearings on the material wants of life, but in its gen- eral influence on the mtellectual advancement of rnankmd, we find its noblest and most important result to be a knowl- edge of the chain of connection, by which all natural forces are linked together, and made mutually dependent upon each other ; and it is the perception of these relations that exalts our views and ennobles our enjoyments. Such a result can, however, only be reaped as the fruit of observation and intel- lect, combined wdth the spirit of the age, in which are reflect- ed all the varied phases of thought. He who can trace, through by-gone times, the stream of our knowledge to its primitive source, will learn from history how, for thousands of years, man has labored, amid the ever-recurring changes of form, to recognize the invariability of natural laws, and has thus, by the force of mind, gradually subdued a great por- tion of the physical world to his dominion. In interrogating the history of the past, we trace the mysterious course of ideas yielding the first glimmering perception of the same imag'i of

24 COSMOS.

a Cosmos, or harmoniously ordered whole, which, dimly shad- owed forth to the human mind in the primitive ages of the world, is now fully revealed to the maturer intellect of man kind as the result of long and laborious observation.

Each of these epochs of the contemplation of the external Vorld — the earliest dawn of thought and the advanced stage of civilization — has its oWii source of enjoyment. In the former, this enjoyment, in accordance with the simplicity of the primitive ages, flowed from an intuitive feeling of the or der that was proclaimed by the invariable and successive re- appearance of the heavenly bodies, and by the progressive de- velopment of organized beings ; while in the latter, this sense of enjoyment springs from a definite knowledge of the phe- nomena of nature. When man began to interrogate nature, and, not conteijt with observing, learned to evoke phenomena under definite conditions ; when once he sought to collect and record facts, in order that the fruit of liis labors might aid in- vestigation after his own brief existence had passed aw^ay, the philosophy of Nature cast aside the vague and poetic garb in which she had been enveloped from her origin, and, having assumed a severer aspect, she now w^eighs the value of ob- servations, and substitutes induction and reasoning for con- jecture and assumption. The dogmas of former ages survive now only in the superstitions of the people and the prejudices of the ignorant, or are perpetuated in a few systems, which, conscious of their weakness, shroud themselves in a vail of mystery. We may also trace the same primitive intuitions in lanffuaofes exuberant in fisfurative exDressions ; and a few of the best chosen symbols engendered by the happy inspira- tion of the earliest ages, having by degrees lost their vague- ness through a better mode of interpretation, are still preserved among our scientific terms.

Nature considered rationally, that is to say, submitted to the process of thought, is a unity in diversity of phenomena ; a harmony, blending together all created things, however dis- similar in form and attributes ; one great whole {to -rrdv) an- imated by the breath of life. The most important result of a rational inquiry into nature is, therefore, to establish the unity and harmony of this stupendous mass of force and mat- ter, to determine with impartial justice what is due to the discoveries of the past and to those of the present, and to an- alyze the individual parts of natural phenomena without suo- cumbing beneath the weight of the whole. Thus, and thus alone, is it permitted to man, while mindful of the high des-

INTRODUCTION. 25

tiny of his race, to comprehend nature, to lift the vail that shrouds her phenomena, and, as it were, submit the results of observation to the test of reason and of intellect.

In reflecting upon the different degrees of enjoyment pre- sented to us in the contemplation of nature, we find that the ftrst place must be assigned to a sensation, which is wholly mdependent of an intimate acquaintance with the physical phenomena presented to our view, or of the peculiar character of the region surrounding us. In the uniform plain bounded only by a distant horizon, where the lowly heather, the cistus, or waving grasses, deck the soil ; on the ocean shore, where the waves, softly rippling over the beach, leave a track, green with the weeds of the sea ; every where, the mind is penetra- ted by the same sense of the grandeur and vast expanse of nature, revealing to the soul, by a mysterious inspiration, the existence of laws that regulate the forces of the universe. Mere communion with nature, mere contact with the free air, exercise a soothing yet strengthening influence on the wearied spirit, calm the storm of passion, and soften the heart when shaken by sorrow to its inmost depths. Every where, in ev ery region of the globe, in every stage of intellectual culture, the same sources of enjoyment are alike vouchsafed to man. The earnest and solemn thoughts awakened by a communion with nature intuitively arise from a presentiment of the order and harmony pervading the whole universe, and from the contrast we draw between the narrow limits of our own ex- istence and the image of infinity revealed on every side, wheth- er we look upward to the starry vault of heaven, scan the far- stretching plain before us, or seek to trace the dim horizon across the vast expanse of ocean.

The contemplation of the individual characteristics of the landscape, and of the conformation of the land in any definite region of the earth, gives rise to a different source of enjoy- ment, awakening impressions that are more vivid, better de- fined, and more congenial to certain phases of the mind, than those of which we have already spoken. At one time the hiiart is stirred by a sense of the grandeur of the face of na- ture, by the strife of the elements, or, as in Northern Asia, by the aspect of the dreary barrenness of the far-stretching steppes ; at another time, softer emotions are excited by the contempla- tion of rich harvests wrested by the hand of man from the wild fertility of nature, or by the sight of human habitations raised beside some wild and foaming torrent. Here I regard less the degree of intensity than the difference existing in the

Vol. I.— B

26 COSMOS.

various sensations that derive their charm and peimauencf from the pecuhar character of the scene.

If I might be allowed to abandon myself to the recollections »f my own distant travels, I would instance, among the most •■■triking scenes of nature, the calm sublimity of a tropical night, ivhen the stars, not sparkling, as in our northern skies, shed cheir soft and planetary light over the gently-heaving ocean ; )r I would recall the deep valleys of the Cordilleras, where ",he tall and slender palms pierce the leafy vail around them, ind waving on high their feathery and arrow-like branches, ';brm, as it were, " a forest above a forest ;"* or I would de- scribe the summit of the Peak of TenerifTe, when a horizontal .ayer of clouds, dazzling in whiteness, has separated the cone )f cinders from the plain below, and suddenly the ascending iurrent pierces the cloudy vail, so that the eye of the traveler may range from the brink of the crater, along the vine-clad slopes of Orotava, to the orange gardens and banana groves that skirt the shore. In scenes like these, it is not the peace- ful charm uniformly spread over the face of nature that moves the heart, but rather the peculiar physiognomy and conforma- tion of the land, the features of the landscape, the ever-vary- ing outline of the clouds, and their blending with the horizon of the sea, whether it lies spread before us like a smooth and shining mirror, or is dimly seen through the morning mist. All that the senses can but imperfectly comprehend, all that is most awful in such romantic scenes of nature, may become 1 source of enjoyment to man, by opening a wide field to the creative powers of his imagination. Impressions change with the varying movements of the mind, and we are led by a hap- py illusion to believe that we receive from the external world that with which we have ourselves invested it.

When far from our native country, after a long voyage, we ;read for the first time the soil of a tropical land, v/e expe- •ience a certain feeling of surprise and gratification in recog- lizing, in the rocks that surround us, the same inclined schis- I ose strata, and the same columnar basalt covered with cellu- iar amygdaloids, that we had left in Europe, and whose iden- iity of character, in. latitudes so widely different, reminds us !.hat the solidification of the earth's crust is altogether inde- [leudent of climatic influences. But these rocky masses of schist and of basalt are covered with vogetation of a character with wluch we are unacquainted, and of a physiognomy wholly

* This expression is taken from a beautiful description of tropical forest sceiieiy iu Paul and Virginia, by Bernardin de Saint Pierre.

INTRODUCTION. 27

unknown to us ; and it is then, amid the colossal and majestic forms of an exotic flora, that we feel how wonderfully the flex- ibility of our nature fits us to receive new impressions, linked together by a certain secret analogy. We so readily perceive the affinity existing among all the forms of organic life, thai although the sight of a vegetation similar to that of our native country might at first be most welcome to the eye, as the sweel familiar sounds of our mother tongue are to the ear, we nev- ertheless, by degrees, and almost imperceptibly, become famil iarized with a new home and a new climate. As a true citi zen of the world, man eveiy where habituates himself to tha' which surrounds him ; yet fearful, as it were, of breaking tl ^ links of association that bind him to the home of his childhood, the colonist applies to some few plants in a far-distant clime the names he had been familiar Avith in his native land ; and by the mysterious relations existing among all types of organiza- tion, the forms of exotic vegetation present themselves to his mind as nobler and more perfect developments of those he had loved in earher days. Thus do the spontaneous impressions of the untutored mind lead, like the laborious deductions of cultivated intellect, to the same intimate persuasion, that one sole and indissoluble chain binds together all nature.

It may seem a rash attempt to endeavor to separate, into its different elements, the magic power exercised upon our minds by. the physical world, since the character of the land- scape, and of every imposing scene in nature, depends so ma- terially upon the mutual relation of the ideas and sentiments simultaneously excited in the mind of the observer.

The powerful effect exercised by nature springs, as it were, from the connection and unity of the impressions and emo- tions produced ; and we can only trace their different sources by analyzing the individuality of objects and the diversity of forces.

The richest and most varied elements for pursuing an anal- ysis of this nature present themselves to the eyes of the trav- eler in the scenery of Southern Asia, in the Great Indian Archipelago, and more especially, too, in the New Continent, where the summits of the lofty Cordilleras penetrate the con- fines of the aerial ocean surrounding our globe, and where the same subterranean forces that once raised these mountain chains still shake them to their foundation and threaten their downfall.

Graphic delineations of nature, arranged according to sys- teraatic views, are not only suited to please the imagination,

28 COSMOS.

but may also, when properly considered, indicate the grades of the impressions of which I have spoken, from the miiform- ity of the sea-shore, or the barren steppes of Siberia, to the inexhaustible fertility of the torrid zone. If we were even to picture to ourselves Mount Pilatus placed on the Schreck- horn,* or the Schneekoppe of Silesia on Mont Blanc, we should

* These comparisons are only approximative. The several eleva- tions above the level of the sea are, in accurate numbers, as follows :

The Schneekoppe or Riesenkoppe, in Silesia, about 5270 feet, ac- cording to Hallaschka. The Righi, 5902 feet, taking the height of the Lake of Lucerne at 1426 feet, according to Eschman. (See Compte Rendu des Mesures Ti-igonometriques en Suisse, 1840, p. 230.) Mount Athos, 6775 feet, according to Captain Gaultier; Mount Pilatus, 7546 feet; Mount ^Etna, 10,871 feet, according to Captain Smyth; or 10,874 feet, according to the barometrical measurement made by Sir John Herschel, and communicated to me in writing in 1825, and 10,899 feet, according to angles of altitude taken by Cacciatore at Palermo (calcu- lated by assuming the terrestrial refraction to be 0'076) ; the Schreck horn, 12,383 feet; the Jungfrau, 13,720 feet, according to TraUes ; Mont Blanc, 15,775 feet, according to the diflferent measurements considered by Roger {Bibl. Univ., May, 1828, p. 24-53), 15,733 feet, according to the measurements taken from Mount Columbier by Carlini in 1821, and 15,748 feet, as measured by the Austrian engineers from Trelod and the Glacier d'Ambin.

The actual height of the Swiss mountains fluctuates, according to Eschman's observations, as much as 25 English feet, owing to the vary- ing thickness of the stratum of snow that covers the summits. Chim- borazo is, according to my trigonometrical measurements, 21,421 feet (see Humboldt, Recueil d^Obs. Astr., tome i., p. 73), and Dhawalagiri, 28,074 feet. As there is a dilference of 445 feet between the determin- ations of Blake and Webb, the elevation assigned to the Dhawalagiri (or white mountain, from the Sanscrit dhawala, white, and giri, mount- ain) can not be received with the same confidence as that of the Jawa- hir, 25,749 feet, since the latter rests on a complete trigonometrical measurement (see Herbert and Hodgson in the Asiat. Res., vol. xiv., p. 189, and Suppl. to Encycl. Brit., vol. iv., p. 643). I have shown elsewhere {Ann. des Sciences Naturelles, Mars, 1825) that the height of the Dhawalagiri (28,074 feet) depends on several elements that have not been ascertained with certainty, as azimuths and latitudes (Hum- boldt, Asie Centrale, t. iii., p. 282). It has been believed, but without foundation, that in the Tartaric chain, north of Thibet, opposite to the chain of Kuen-lun, there are several snowy summits, whose elevation is about 30,000 English feet (almost twice that of Mont Blanc), or, at any rate, 29,000 feet (see Captain Alexander Gerard's and John Gerard's J(>- '•ney to the Boorendo Pass, 1840, vol. i., p. 143 and 311). Chimbo- ru-^o is spoken of in the text only as one of the highest summits of the chain of the Andes; for in the year 1827, the learned and highly-gifted traveler, Pentland, in his memorable expedition to Upper Peru (Bolivia), measured the elevation of two mountains situated to the east of Lake Titicaca, viz., the Sorata, 25,200 feet, and the Illimani, 24,000 feet, both greatly exceeding th« height of Chimborazo, which is only 21,421 feet, and being nearly equal in elevation to the Jawahir, which is the highest mouutaia in the Himalaya that has as yet been accurately measured.

INTRODUCTION. 29

not have attained to the height of that great Colossus of the Andes, the Chimhorazo, whose height is twice that of Mount ^tna; and we must pile the Righi, or Mount Athos, on the summit of the Chimhorazo, in order to form a just estimate of the elevation of the Dhawalagiri, the highest point of the Himalaya. But although the mountains of India greatly sur- pass the Cordilleras of South America hy their astonishing el- evation (which, after heing long contested, has at last been confirmed by accurate measurements), they can not, from their geographical position, present the same inexhaustible variety of phenomena by which the latter are characterized. The impression produced by the grander aspects of nature does not depend exclusively on height. The chain of the Himalaya is placed far beyond the limits of the torrid zone, and scarcely is a solitary palm-tree to be found in the beautiful valleys of Kumaoun and Garhwal.* On the southern slope of the an- cient Paropamisus, in the latitudes of 28^ and 34°, nature no longer displays the same abundance of tree-ferns and arbores- cent grasses, heliconias and orchideous plants, which in tropic-

Thus Mont Blanc is 5646 feet below Chimborazo ; Chimhorazo, 3770 feet below the Sorata ; the Sorata, 549 feet below the Jawahir, and prob ably about 2880 feet below the Dhawalagiri. According to a new measurement of the Illimani, by Pentland, in 1838, the elevation of this mountain is given at 23,868 feet, varying only 133 feet from the meas- urement taken in 1827. The elevations have been given in this note with minute exactness, as erroneous numbers have been introduced into many maps and tables recently published, owing to incorrect re- ductions of the measux'ements.

[In the preceding note, taken from those appended to the Introduc- tion in the French translation, rewritten by Humboldt himself, the measurements are given in meters, but these have been convei'ted into English feet, for the greater convenience of the general reader.] — Tr.

* The absence of palms and tree-ferns on the temperate slopes of the Himalaya is shown in Don's Flora Nepalensis, 1825, and in the remark- able series of lithographs of WalUch's Flora Indica, whose catalogue contains the enormous number of 7683 Himalaya species, almost all phanerogamic plants, which have as yet been but imperfectly classified. In Nepaul (lat. 26^° to 27^°) there has hitherto been observed only one species of palm, Chamaerops martiana, Wall. {Plaidce Asiat., lib. iii., p 5, 211), which is found at the height of 5250 English feet above the level of the sea, in the shady valley of Bunipa. The magnificent tree-fern, Alsophila bmnoniaua, Wall, (of which a stem 48 feet long has been in the possession of the British Museum since 1831), does not grow in Ne- paul, but is found on the mountains of Silhet, to the northwest of Cal- cutta, in lat. 24° 50'. The Nepaul fern, Paranema'cyathoides, Don, formerly known as Sphaeroptera barbata, Wall. {Plantce Asiat., lib. i., p. 42, 48). is, indeed, nearly related to Cyathea, a species of which I have seen in the South American Missions of Caripe, measm-ing 33 feet in height; this is not, however, properly speaking, a tree.

30 CO&MOS.

al regions are to be found even on the highest plateaux of the mountains. On the slope of the Himalaya, under the shade of the Deodora and the broad-leaved oak, peculiar to these Indian Alps, the rocks of granite and of mica schist are cov- ered with vegetable forms almost similar to those which char- acterize Europe and Northern Asia. The species are not identical, but closely analogous in aspect and physiognomy, as, for instance, the juniper, the alpine birch, the gentian, the marsh parnassia, and the prickly species of Ribes.* The chain of the Himalaya is also wanting in the imposing phe- nomena of volcanoes, which in the Andes and in the Indian Archipelago often reveal to the inhabitants, under the most terrific forms, the existence of the forces pervading the inte- rior of our planet.

Moreover, on the southern declivity of the Himalaya, where the ascending current deposits the exhalations rising from a vigorous Indian vegetation, the region of perpetual snow be- gins at an elevation of 11,000 or 12,000 feet above the level of the sea,t thus setting a limit to the development of organic

** Ribes iiubicola, R. glaciale, R. grossularia. The species which compose the vegetation of the Himalaya are four pines, notwithstanding the assertion of the ancients regarding Eastern Asia (Strabo, lib. 11, p. 510, Cas.), twenly-five oaks, four birches, two chestnuts, seven maples, twelve willows, fourteen roses, three species of strawberry, seven spe- cies of Alpine roses (rhododendra), one of which attains a height of 20 feet, and many other northern genera. Large white apes, having black faces, inhabit the wild chestnut-tree of Kashmir, which grows to a height of 100 feet, in lat. 33° (see Carl von HUgel's Kasckmir, 1840, 2d pt. 249). Among the Coniferae, we find the Pinus deodwara, or deodara (in Sanscrit, dewa-dar^i, the timber of the gods), which is nearly allied to Pinus cedrus. Near the limit of perpetual snow flourish the large and showy flowers of the Gentiana venusta, G. Moorcroftiaua, Swertia purpurescens, S. speciosa, Parnassia armata, P. nubicola, Poeonia Emo- di, Tulipa stellata; and, besides varieties of European genera peculiar to these Indian mountains, true European species, as Leontodon tarax- acum, Prunella vulgaris, Galium aparine, and Thlaspi arvense. The heath mentioned by §aunders, in Turner's Travels, and which had been confounded with Calluna vulgaris, is an Andromeda, a fact of the great- est importance in the geography of Asiatic plants. If I have made use, in this work, of the uuphilosophical expressions of Ejiropean genera, European species, growing wild in Asia, &c., it has been in consequence of the old botanical language, which, instead of the idea of a large dis- semination, or, rather, of the coexistence of organic productions, has dogmatically substituted the false hypothesis of a migration, which, fi'om predilection*for Europe, is further assumed to have been from west to east,

t On the southern declivity of the Himalaya, the limit of perpetual Buow is 12,978 feet above the level of the sea; on the northern decliv- ity, or, rather, on the peaks which rise above the Thibet, or Tartarian

INTKUIJUCIION. 3)

ahi in a zone that is nearly 3000 feet lower than that to which it attains in the equinoctial region of the Cordilleras.

plateau, this limit is at 16,625 feet from 20^° to 32° of latitude, whilt Bt the equator, iu the Andes of Quito, it is 15,790 feet. Such is the resuh I have deduced from the combiuatiou of numerous data famished by Webb, Gerard, Herbert, and Moorcroft. (See my two memoirs on the mountains of India, in 1816 and 1820, iu the Ann. de CJdmie et di Physique, t. iii., p- 303 ; t. xiv., p. 6, 22, 50.) The greater elevation to which the Hmit of perpetual snow recedes on the Tartarian declivity is owing to tlie radiation of heat from the neighboring elevated plains, to tlie purity of the atmosphere, and to the infrequent formation of snow in an air which is both very cold and veiy dry. (Humboldt, Asie Cen trale, t. iii., p. 281-326.) My opinion on the ditference of height of the snow-line on the two sides of the Himalaya has the high authority of Colebrooke in its favor. He wrote to me in June, 1824, as follows: " I also find, from the data in my possession, that the elevation of the iiue of perpetual snow is 13,000 feet. On the southern declivity, and at latitude 31*^, Webb's measurements give me 13,500 feet, consequently 500 i'eet more than the height deduced from Captain Hodgson's oh servations. Gerard's measurements fully confirm your opinion tha' the hue of snow is higher on the northern than on the southern side.' <t was not until the present year (1840) that we obtained the complett and collected journal of the brothers Gerard, published under the su pervision of Mr. Lloyd. {Narrative of a Journey from Caionpoor h the Boorendo Pass, in the Himalaya, by Captain Alexander Gerard ant John Gerard, edited by George Lloyd, vol. i., p. 291, 311, 320, 327, an< ^Ml.) Many interesting details regarding some localities may be fount ■ in tlie narrative of A Visit to the Shatool,for the Ptirpose of determinin. the Line of Perpetual Stiow on the southern face of the Himalaya, in At gust, 1822. Unfortunately, however, these travelers always confoun the elevation at which sporadic snow falls with the maximum of th height that the snow-line attains on the Thibetian plateau. Captaii Gerard distinguishes between the summits that rise in the middle o the plateau, where he states the elevation of the snow-line to be b( *ween 18,000 and 19,000 feet, and the northern slopes of the chain o »he Himalaya, which border on the defile of the Sutledge, and can ri diate but little heat, owing to the deep ravines with which they ai ^ intersected. The elevation of the village of Tangno is given at onl » 9300 feet, while that of the plateau surrounding the sacred lake of Mj. nasa is 17,000 feet. Captain Geraixl finds the snow^-line 500 feet lowt >. on the northern slopes, where the chain of the Himalaya is broke i through, than toward the southern declivities facing Hindostan, and h • '.here estimates the line of perpetual snow at 15,000 feet. The moi striking difierences are presented between the vegetation on the Thil etian plateau and that characteristic of the southern slopes ot the Hin alaya. On the latter the cultivation of grain is arrested at 9974 fee. and even there the corn has often to be cut when the blades are sti., green. The extreme limit of forests of tali oaks and deodars is 11,900 feet ; that of dwarf birches, 12,983 feet. On the plains. Captain Gerard found pastures up to the height of 17,000 feet; the cereals will grow ui 14,100 feet, or even at 18,540 feet; birches with tall stems at 14,100 feet, and copse or brush wood applicable for fuel is found at an elevti tioa of upward of 17,000 feet, that is to say, 1280 feet above the lowej limits of the snow-line at the equator, in the province of Quito. It is-

H2 cosMv s.

But the countries bordering on the equator possess anoihei advantage, to which sufficient attentign has not hitherto been

very desirable that the mean elevation of the Thibetiaii plateau, which I have estimated at ouly about 8200 feet between the Himalaya and the Kuen-lun, and the difference in the height of the line of perpetual snow on the southern and on the northern slopes of the Himalaya, should be again ihvestigated by travelers who are accustomed to judge of the general conformation of the land. Hitherto simple calculations have too often been confounded with actual measurements, and the elevations of isolated summits with that of the surrounding plateau. (Compare Carl Zimmerman's excellent Hypsometrical Kemarks in his Geograph- isclien Analyse der Karte von Inner Asien, 1841, s. 08.) Lord draws attention to the difference presented by the two faces of the Himalaya and those of the Alpine chain of Hindoo-Coosh, with respect to the limits of the snow-line. " The latter chain," he says, "has the table- land to the south, in consequence of which the snow-line is higher on the southern side, contrary to what we find to be the case with respect to the Himalaya, which is bounded on the south by sheltered plains, as Hindoo-Coosh is on the north." It must,hov/ever,be admitted that the hypsometrical data on which these statements are based require a critical revision with regard to several of their details; but still they sufSce to establish the main fact, that the remarkable configuration of the laud in Central Asia affords man all that is essential to the mainte- nance of life, as habitation, food, and fuel, at an elevation above the level of the sea which in almost all other parts of the globe is covered with perpetual ice. We must except the very dry districts of Bolivia, where snow is so rarely met with, and where Pentland (in 1838) fixed the snov/-line at 15,667 feet, between 16° and 17|° south latitude. The opinion that I had advanced regarding the difference in the snow-line on the two faces of the Himalaya has heen most fully confirmed by the barometrical observations of Victor Jacquemont, who fell an early sac- I'ifice to his noble and unwearied ardor. (See his Correspondanc& pendant son Voyage dans V Inde, 1828 a 1832, hv. 23, p. 290, 296,299.) " Perpetual snow," says Jacquemont, " descends lower on the southern than on the northern slopes of the Himalaya, and the limit constantly? rises as we advance to the north of the chain bordering on India. On the Kioubrong, about 18,317 feet in elevation, according to Captain Gerard, I was still considerably below the limit of perpetual snow, which I believe to be 19,690 feet in this part of Hindostan." (This estimate I consider much too high.)

The same ti-aveler says, " To whatever height we rise on the south- ern declivity of the Himalaya, the climate retains the same character, and the same division of the seasons as in the plains of India ; the sum- mer solstice being eveiy year marked by the same prevalence of rain, w^hich continues to fall without intermission until the autumnal equi- nox. But a new, a totally different climate begins at Kashmir, whose elevation I estimate to be 5350 feet, nearly equal to that of the cities of Mexico and Popayan" {Correspond, de Jacquemont, t. ii., p. 58 et 74), The warm and humid air of the sea, as Leopold von Buch well observes, is carried by the monsoons across the plains of India to the skirts of the Himalaya, which arrest its couise, and hinder it from diverging to the Thibetian districts of Ladak and Lassa. Carl von HUgel estimates the elevation of the Valley of Kashmir above the level of the sea at 5818 feet, and bases his observation on the determination of the boiling

INTRODUCTION. 33

directed. This portion of the surface of the globe affords in the smallest space the greatest possible variety of impressions from the contemplation of nature. Among the colossal mount- ains of Cundinamarca, of Quito, and of Peru, furrowed by deep ravines, man is enabled to contemplate alike all the fam- ilies of plants, and all the stars of the firmament. There, at a single glance, the eye surveys majestic palms, humid forests of bambusa, and the varied species of Musacese, while above these forms of tropical vegetation appear oaks, medlars, the sweet-brier, and umbelliferous plants, as in our European homes. There, as the traveler turns his eyes to the vault of heaven, a single glance embraces the constellation of the South- ern Cross, the Magellanic clouds, and the guiding stars of the constellation of the Bear, as they circle round the arctic pole. There the depths of the earth and the vaults of heaven dis- play all the richness of their forms and the variety of their phenomena. There the different climates are ranged the one above the other, stage by stage, like the vegetable zones, whose succession they limit ; and there the observer may readily trace the laws that regulate the diminution of heat, as they stand indelibly inscribed on the rocky walls and abrupt decliv- ities of the Cordilleras.

Not to M'-eary the reader with the details of the phenomena which I long since endeavored graphically to represent,* I will here limit myself to the consideration of a few of the gen- eral results whose combination constitutes the i^liy^ical delhie- ation of the torrid zone. That which, m the vagueness of our

point of water (see theil 11, s. 155, and Journal of Geog. Soc, vol. vi., p. 215). In this valley, where the atmosphere is scarcely ever agita- ted by storms, and in 34° 7' lat., snow^ is found, several feet in thick- ness, from December to March.

* See, generally, my Essai sur la Geographie des Plantes, et le Ta- bleau physique des Regions Equinoxiales, 1807, p. 80-88. On the diur- nal and nocturnal variations of temperatui'e, see Plate 9 of my Atlas Geogr. et Phys. du Nouveau Continent; and the Tables in my work, entitled De distributione Geographica Plantarum, secundum cosli tempe- riem, et altitudinem Montium, 1817, p. 90-116 ; the meteorological por- tion of my Asie Centrale, t. iii., p. 212, 224; and, finally, the more receut and far more exact exposition of the variations of temperature experienced in correspondence with the increase of altitude on the chain of the Andes, given in Boussiugault's Memoir, Sur la profondeur a la- quelle on trouve, sous les Tropiques, la coucke de Temperature Invaria- ble. (Ann. de Chimie et de Physique, 1833, t. liii., p. 225-247.) This treatise contains the elevations of 128 points, included between the level of the sea and the declivity of the Antisana (17,900 feet), as well as the mean temperature of the atmosphere, which varies with the height between 81° and 35° F.

B2

34 COSMOS.

impressions, loses all distinctness of form, like some distant mountain shrouded from view by a vail of mist, is clearly re- vealed by the light of mind, which, by its scrutiny into the causes of phenomena, learns to resolve and analyze their dif- ferent elements, assigning to each its individual character. Thus, in the sphere of natural investigation, as in poetry and painting, the delineation of that which appeals most strong- ly to the imagination, derives its collective interest from the vivid truthfulness with which the individual features are por- trayed.

The regions of the torrid zone not only give rise to the most powerful impressions by their organic richness and their abundant fertility, but they likewise afford the inestimable advantage of revealing to man, by the uniformity of the vari- ations of the atmosphere and the development of vital forces, and by the contrasts of climate and vegetation exhibited at different elevations, the invariability of the laws that regulate the course of the heavenly bodies, reflected, as it were, in ter- restrial phenomena. Let us dwell, then, for a few moments, on the proofs of this regularity, which is such that it may be submitted to numerical calculation and computation.

In the burning plains that rise but little above the level of the sea, reign the families of the banana, the cycas, and the palm, of wliich the number of species comprised in the flora of tropical regions has been so wonderfully increased in the present day by the zeal of botanical travelers. To these groups succeed, in the Alpine valleys, and the humid and shaded clefts on the slopes of the Cordilleras, the tree-ferns, whose thick cylindrical trunks and delicate lace-like foliage stand out in bold relief against the azure of the sky, and the cinchona, from which we derive the febrifuge bark. The medicinal strength of this bark is said to increase in propor- tion to the degree of moisture imparted to the foliage of the tree by the light mists which form the upper surface of the clouds resting over the plains. Every where around, the con- fines of the forest are encircled by broad bands of social plants, as the delicate aralia, the thibaudia, and the myrtle-leaved Andromeda, while the Alpine rose, the magnificent befaria, weaves a purple girdle round the spiry peaks. In the cold regions of the Paramos, which is continually exposed to the fury of storms and winds, we find that flowering shrubs and herbaceous plants, bearing large and variegated blossoms, h^ve given place to monocotyledons, whose slender spikes con- it"*,ute the sole covering of the soil. This is the zone of the

INTRODUCTION. 35

glasses, one vast savannah extending over the immense mount- ain-plateaux, and reflecting a yellow, almost golden tinge, tc the slopes of the Cordilleras, on which graze the lama and the cattle domesticated by the European colonist. Where the naked trachyte rock pierces the grassy turf, and penetrates into those higher strata of air which are supposed to be less charged with carbonic acid, we meet only with plants of an inferior or- ganization, as lichens, lecideas, and the brightly-colored, dust- like lepraria, scattered around in circular patches. Islets of fresh-fallen snow, varying in form and extent, arrest the last feeble traces of vegetable development, and to these succeeds the region of perpetual snow, whose elevation undergoes but little change, and may be easily determined. It is but rarely that the elastic forces at work within the interior of our globe have succeeded in breaking through the spiral domes, which, resplendent in the brightness of eternal snow, crown the sum- mits of the Cordilleras ; and even where these subterranean forces have opened a permanent communication with the at- mosphere, through circular craters or long fissures, they rarelj send forth currents of lava, but merely eject ignited scoriae, steam, sulphureted hydrogen gas, and jets of. carbonic acid.

In the earhest stages of civilization, the grand and imposing spectacle presented to the minds of the inhabitants of the trop- ics could only awaken feelings of astonishment and awe. Il might, perhaps, be supposed, as we have already said, that the periodical return of the same phenomena, and the uniform man- ner in which they arrange themselves in successive groups, would have enabled man more readily to attain to a knowl- edge of the laws of nature ; but, as far as tradition and history guide us, we do not find that any application was made of the advantages presented by these favored regions. Recent re- searches have rendered it very doubtful whether the primitive seat of Hindoo civihzation — one of the most remarkable phase.' in the progress of mankind — was actually within the tropics Airyana Vaedjo, the ancient cradle of the Zend, was situatec to the northwest of the upper Indus, and after the great re ligious schism, that is to say, after the separation of the Ir:i uians from the Brahminical institution, the language that ha« previously been common to them and to the Hindoos assume' among the latter people (together with the hterature, habit: and condition of society) an individual form in the Magodha oi Madhya Desa,* a district that is bounded" by the great chaii.

* See, on the Madhjadecja, properly so called, Lassen's exceilei work, entitled Indische Altcrthumskun'de, bd. i., s. 92. The Chinest

S6 cosivros.

oi' Himalaya and the smaller range of the Vindhya. In less ancient times the Sanscrit language and civilization advanced tovi^ard the southeast, penetrating further within the torrid zone, as my brother Wilhelm von Humboldt has shov^^n in his great work on the Kavi and other languages of analogous structure.*

Notwithstanding the obstacles opposed in northern latitudes to the discovery of the laws of nature, owing to the excessive complication of phenomena, and the perpetual local variations that, in these climates, afiect the movements of the atmosphere and the distribution of organic forms, it is to the inhabitants of a small section of the temperate zone that the rest of man- kind owe the earliest revelation of an intimate and rational acquaintance with the forces governing the physical world. Moreover, it is from the same zone (which is apparently more favorable to the progress of reason, the softening of manners, and the security of public liberty) that the germs of civiliza- tion have been carried to the regions of the tropics, as much by the migratory movement of races as by the establishment of colonies, differing widely in their institution from those of the Phoenicians or Greeks.

In speaking of the influence exercised by the succession of phenomena on the greater or lesser facility of recognizing the causes producing them, I have touched upon that important stage of our communion with the external world, when the en- joyment arising from a knowledge of the laws, and the mutual connection of phenomena, associates itself with the charm of a simple contemplation of nature. That which for a long time remains merely an object of vague intuition, by degrees acquires the certainty of positive truth ; and man, as an im- mortal poet has said, in our own tongue — Amid ceaseless change seeks the unchanging pole.f

In order to trace to its primitive source the enjoyment de- rived from the exercise of thought, it is sufficient to cast a J:apid glance on the earliest dawnings of the philosophy of na- ture, or of the ancient doctrine of the Cosmos. We find even

give the name of Mo-kie-thi to the southern Bahar, situated to the south of the Ganges (see Foe-Koue-Ki, by Chy-Fa-Hian, 1836, p. 256). Djambu-dwipa is the name given to the whole of India; but the words also indicate one of the four Buddhist continents.

* Ueber die Kawi Sprache aiif der Insel Java, nebst einer Einleiijinff iiber die Verschiedenheit des menschlichen Spra^'hbaiies und ihren Ein fluss auf die geistige Entwickelung des Mensckengeschlechf s, von Wil helm V. Humboldt, 1836, bd. i., s. 5-510.

t This verse occurs in a poem of Schiller, entitled Der Spaziergayig which first appeared in 1795, in the Horen.

INTRODUCTION. 37

among the most savage nations (as my own travels enable me to attest) a certain vague, terror-stricken sense of the all-pow- erful unity of natural forces, and of the existence of an invisi- ble, spiritual essence manifested in these forces, whether in unfolding the flower and maturing the fruit of the nutrient tree, in upheaving the soil of the forest, or in rending the clouds with the might of the storm. We may here trace the revela- tion of a bond of union, linking together the visible world and that higher spiritual world which escapes the grasp of the senses. The two become unconsciously blended together, de- veloping in the mind of man, as a simple product of ideal con- ception, and independently of the aid of observation, the first germ of a Fhiloioiohy of Nature.

Among nations least advanced in civilization, the imagina- tion revels in strange and fantastic creations, and, by its pre- dilection for symbols, alike influences ideas and language. In- stead of examining, men are led to conjecture, dogmatize, and interpret supposed facts that have never been observed. The inner world of thought and of feelins: does not reflect the imajje of the external world in its primitive purity. That which in some regions of the earth manifested itself as the rudiments of natural philosophy, only to a small number of persons en- dowed with superior inteUigence, appears in other regions, and among entire races of men, to be the result of mystic tenden- cies and instinctive intuitions. An intimate communion with nature, and the vivid and deep emotions thus awakened, are likewise the source from which have sprung the first impulses toward the worship and deification of the destroying and pre- serving forces of the universe. But by degrees, as man, after having passed through the different gradations of intellectual development, arrives at the free enjo}rment of the regulating power of reflection, and learns by gradual progress, as it were, to separate the world of ideas from that of sensations, he no longer rests satisfied merely with a vague presentiment of the harmonious unity of natural forces ; thought begins to fulfill its noble mission ; and observation, aided by reason, endeav- ors to trace phenomena to the causes from which they spring

The history of science teaches us the difficulties that have opposed the progress of this active spirit of inquiry. Inaccu rate and imperfect observations have led, by false inductions, to the great number of physical views that have been perpet- uated as popular prejudices among all classes of society. Thus by the side of a solid and scientific knowledge of natural phe- nomena there has been preserved a system of the pretended

38 COSMOS.

results of observation, which is so much the more difficult to shake, as it denies the vahdity of the facts by which it may be refuted. This empiricism, the melancholy heritage trans- mitted to us from former times, invariably contends for the truth of its axioms with the arrogance of a narrow-minded spirit. Physical philosophy, on the other hand, when based upon science, doubts because it seeks to investigate, distin- guishes between that which is certain and that which is mere- ly probable, and strives incessantly to perfect theory by ex- tending the circle of observation.

This assemblage of imperfect dogmas, bequeathed by one- age to another — this physical philosophy, which is composed of popular prejudices — is not only injurious because it perpet- uates error with the obstinacy engendered by the evidence of ill-observed facts, but also because it hinders the mind from attaining to higher views of nature. Instead of seeking to discover the mean or medium point, around which oscillate, in apparent iiidependence offerees, all the phenomena of the external world, this system delights in multiplying exceptions to the law, and seeks, amid phenomena and in organic forms, for something beyond the marvel of a regular succession, and an internal and progressive development. Ever inclined to beheve that the order of nature is disturbed, it refuses to rec ognize in the present any analogy with the past, and, guided by its own varying hypotheses, seeks at hazard, either in the interior of the globe or in the regions of space, for the cause of these pretended perturbations.

It is the special object of the present work to combat those errors which derive their source Irom a vicious empiricism and from imperfect inductions. The higher enjoyments yielded by the study of nature depend upon the correctness and the depth of our views, and upon the extent of the subjects that maybe comprehended in a single glance. Increased mental cultiva- tion has given rise, in all classes of society, to an increased de- sire of embellishing life by augmenting the mass of ideas, and by multiplying means for their generalization ; and this sen- timent fully refutes the vague accusations advanced against the age in which we live, showing that other interests, be- sides the material wants of life, occupy the minds of men.

It is almost with reluctance that I am about to speak of a sentiment, which appears to arise from narrow-minded views, or from a certain weak and morbid sentimentality — I alludo to thejTear entertained by some persons, that nature rnay by degrees lose a portion of the charm and magic of her power.

INTRODUCTION. 39

4S we learn more and more how to nnvail her secrets, com- prehend the mechanism of the movements of the heavenly bodies, and estimate numerically the intensity of natural forces. It is true that, properly speaking, the forces of nature can only exercise a magical power over us as long as their action is ehrouded in mystery and darkness, and does not admit of be- mg classed among the conditions with which experience has made us acquainted. The effect of such a power is, there- fore, to excite the imagination, but that, assuredly, is not the faculty of mind we would evoke to preside over the laborious and elaborate observations by which we strive to attain to a knowledge of the greatness and excellence of the laws of the universe.

The astronomer who, by the aid of the heliometer or a double-refracting prism,* determines the diameter of planetary bodies ; who measures patiently, year after year, the meridian altitude and the relative distances of stars, or who seeks a tel escopic comet in a group of nebulae, does not feel his imagina- tion more excited — and this is the very guarantee of the pre- cision of his labors — than the botanist who counts the divi- sions of the calyx, or the number of stamens in a flower, or ex- amines the connected or the separate teeth of the peristoma surrounding the capsule of a moss. Yet the multiplied an- gular measurements on the one hand, and the detail of organic relations on the other, alike aid in preparing the way for the attainment of higher views of the laws of the universe.

We must not confound the disposition of mind in the ob- server at the time he is pursuing his labors, with the ulterior greatness of the views resulting from investigation and the exercise of thought. The physical philosopher measures with admirable sagacity the waves of light of unequal length which by interference mutually strengthen or destroy each other, even with respect to their chemical actions ; the astronomer, armed with powerful telescopes, penetrates the regions of space, contemplates, on the extremest confines of our solar system, the satellites of Uranus, or decomposes faintly spark- ling points into double stars differing in color. The botanist discovers the constancy of the gyratory motion of the chara in the greater number of vegetable cells, and recognizes in the genera and natural families of plants the intimate relations of organic forms. The vault of heaven, studded with nebu-

* Arago's ocular micrometer, a happy improvement upon Rochou'a prismatic or double-refraction micrometer. See M. Mathieu's note ii Delambre's Histoire de V Astronomic au dix-huUieme Siecle, 1827.

40 COSMOS

IsL' and stars, and the rich vegetable mantle that covers the soil in the climate of palms, can not surely fail to produce on the minds of these laborious observers of nature an impression more imposing and more w^orthy of the majesty of creation than on those who are unaccustomed to investigate the great mutual relations of phenomena. I can not, therefore, agree with Burke when he says, "it is our ignorance of natural things that causes all our admiration, and chiefly excites our passions."

While the illusion of the senses would make the stars sta- tionary in the vault of heaven. Astronomy, by her aspiring la- bors, has assigned indefinite bounds to space ; and if she have set limits to the great nebula to which our solar system be- longs, it has only been to show us in those remote regions of space, which appear to expand in proportion to the increase of our optic powers, islet on islet of scattered nebulce. The feeling of the sublime, so far as it arises from a contemplation of the distance of the stars, of their greatness and physical ex- tent, reflects itself in the feeling of the infinite, which belongs to another sphere of ideas included in the domain of mind. The solemn and imposing impressions excited by this senti- ment are owing to the combination of which we have spoken, and to the analogous character of the enjoyment and emotions awakened in us, whether we float on the surface of the great deep, stand on some lonely mountain summit enveloped in the half transparent vapory vail of the atmosphere, or by the aid of powerful optical instruments scan the regions of space, and see the remote nebulous mass resolve itself into worlds of stars.

The mere accumulation of unconnected observations of de- tails, devoid of generalization of ideas, may doubtlessly have tended to create and foster the deeply-rooted prejudice, that the study of the exact sciences must necessarily chill the feel- ings, and diminish the nobler enjoyments attendant upon a contemplation of nature. Those who still cherish such erro neous views in the present age, and amid the progress of pub- lic opinion, and the advancement of all branches of knowledge, fail in duly appreciating the value of every enlargement of th(; sphere of intellect, and the importance of the detail of isolated facts in leading us on to general results. The fear of sacri ficing the free enjoyment of nature, under the influence of" sci- entific reasoning, is often associated with an apprehension that every mind may not be capable of grasping the truths of the philosophy of nature. It is certainly true that in the midst of the universal fluctuation of phenomena and vital

INTRODUCTION. 41

forces — ill that inextricable net- work of organisms by turns developed and destroyed — each step that we make in the more intimate knowledge of nature leads us to the entrance of new labyrinths ; but the excitement produced by a presenti- ment of discovery, the vague intuition of the mysteries to be unfolded, and the multiplicity of the paths before us, all tend to stimulate the exercise of thought in every stage of knowl- edge. The discovery of each separate law of nature leads to the establishment of some other more general law, or at least indicates to the intelligent observer its existence. Nature, as a celebrated physiologist* has defined it, and as the word was interpreted by the Greeks and Romans, is " that which is ever growing and ever unfolding itself in new forms."

The series of organic types becomes extended or perfected in proportion as hitherto unknown regions are laid open to our view by the labors and researches of travelers and observers ; as living organisms are compared with those which have dis- appeared in the great revolutions of our planet ; and as micro- scopes are made more perfect, and are more extensively and efficiently employed. In the midst of this immense variety, and this periodic transformation of animal and vegetable pro- ductions, we see incessantly revealed the primordial mystery of all organic development, that same great problem of meta- Tnorpliosis which Gothe has treated with more than common sagacity, and to the solution of which man is urged by his desire of reducuiEr vital forms to the smallest number of fun- damental types. As men contemplate the riches of nature, and see the mass of observations incessantly increasing be- fore them, they become impressed with the intimate convic- tion that the surface and the interior of the earth, the depths of the ocean, and the regions of air will still, when thousands and thousands of years have passed away, open to the scien- tific observer untrodden paths of discovery. The regret of Alexander can not be appUed to the progress of observation and intelligence.! General considerations, whether they treat of the agglomeration of matter in the heavenly bodies, or of the geographical distribution of terrestrial organisms, are not only in themselves more attractive than special studies, but they also afford superior advantages to those who are unable to devote much time to occupations of this nature. The dif- ferent branches of the study of natural history are only accessi- ble in certain positions of social life, and do not, at every sea-

* Cams, Von den Urtheilen des Knochen und Schalen Gerustes, 18"2^ $ 6 + Plut., in Vita Alex. Magni, cap. 7

42 COSMOS.

son and m every climate, present like enjoyments. Thus, in the dreary regions of the north, man is deprived for a long period of the year of the spectacle presented by the activity of the productive forces of organic nature ; and if the mind be directed to one sole class of objects, the most animated narratives of voyages in distant lands w^ill fail to interest and attract us, if they do not touch upon the subjects to v^^hich we are most partial.

As the history of nations — if it were always able to trace events to their true causes — might solve the ever-recurring enigma of the oscillations experienced by the alternately pro- gressive and retrograde movement of human society, so might also the physical description of the world, the science of the Co&inos, if it were grasped by a powerful intellect, and based upon a knowledge of all the results of discovery up to a giv- en period, succeed in dispelling a portion of the contradictions which, at first sight, appear to arise from the complication oi phenomena and the multitude of the perturbations simultane- ously manifested.

The knowledge of the laws of nature, whether we can trace them in the alternate ebb and flow of the ocean, in the measured path of comets, or in the mutual attractions of mul- tiple stars, alike increases our sense of the calm of nature, while the chimera so long cherished by the human mind in its early and intuitive contemplations, the belief in a "discord of the elements," seems gradually to vanish in proportion as science extends her empire. General views lead us habitu- ally to consider each organism as a part of the entire creation, and to recognize in the plant or the animal not merely an isolated species, but a form linked in the chain of being to other forms either living or extinct. They aid us in compre- hending the relations that exist between the most recent dis coveries and those which have prepared the way for them. Although fixed to one point of space, we eagerly grasp at a knowledge of that wliich has been observed in different and far-distant regions. We delight in tracking the course of the bold mariner through seas of polar ice, or in following him to the summit of that volcano of the antarctic pole, whose fires may be seen from afar, even at mid-day. It is by an ac- quaintance with the results of distant voyages that we may learn to comprehend some of the marvels of" terrestrial mag- netism, and be thus led to appreciate the importance of the estal lishments of the numerous observatories which in the present day cover both hemispheres, and are designed to note

INTRODUCTION. 43

the simullaiieous occurrence of perturbations, and the frequen- cy and duration of tnagnetic storms.

Let me be permitted here to touch upon a few points con- nected with discoveries, whose importance can only be esti- mated by those who have devoted themselves to the study of the physical sciences generally. Examples chosen from among the phenomena to which special attention has been directed in recent times, will throw additional light upon the preceding considerations. Without a preHminary knowledge of the orbits of comets, we should be unable duly to appre- ciate the importance attached to the discovery of one of these bodies, whose elliptical orbit is included in the narrow limits of our solar system, and which has revealed the existence of an ethereal fluid, tending to diminish its centrifugal force and the period of its revolution.

The superficial half-knowledge, so characteristic of the present day, which leads to the introduction of vaguely com- prehended scientific views into general conversation, also gives rise, under various forms, to the expression of alarm at the supposed danger of a collision between the celestial bodies, or of disturbance in the climatic relations of our globe. These phantoms of the imagination are so much the more injurious as they derive their source from dogmatic pretensions to true science. The history of the atmosphere, and of the annual variations of its temperature, extends already sufficiently far back to show the recurrence of shglit disturbances in the mean temperature of any given place, and thus afibrds suffi- cient guarantee against the exaggerated apprehension of a general and progressive deterioration of the climates of Eu- rope. Encke's comet, which is one of the three interior comets, completes its course in 1200 days, but from the form and position of its orbit it is as little dangerous to the earth as Halley's great comet, whose revolution is not completed in less than seventy-six years (and which appeared less brilliant in 1835 than it had done in 1759) : the interior comet of Biela intersects the earth's orbit, it is true, but it can only approach our globe when its proximity to the sun coincides with our winter solstice.

The quantity of heat received by a planet, and whose un- equal distribution determines the meteorological variations of its atmosphere, depends alike upon the light-engendering force of the sun ; that is to say, upon the conditio-i of its gaseous coverings, and upon the relative position of the planet and the central body.

44 COSMOS.

There are variations, it is true, which, in obedience to the laws of universal gravitation, affect the form of the earth's or- bit and the inclination of the ecliptic, that is, the angle M^hich the axis of the earth makes with the plane of its orbit ; but these periodical variations are so slow, and are restricted with- in such narrow limits, that their thermic effects would hardly be appreciable by our instruments in many thousands of years. The astronomical causes of a refrigeration of our globe, and of the diminution of moisture at its surface, and the nature and frequency of certain epidemics — phenomena which are often discussed in the present 4ay according to the benighted views of the Middle Ages — ought to be considered as beyond the range of our experience in physics and chemistry.

Physical astronomy presents us with other phenomena, which can not be fully comprehended in all their vastness without a previous acquirement of general views regarding the forces that govern the universe. Such, for instance, are the innumerable double stars, or rather suns, which revolve round one common center of gravity, and thus reveal in dis- tant worlds the existence of the Newtonian law ; the larger or smaller number of spots upon the sun, that is to say, the openings formed through the luminous and opaque atmosphere surrounding the solid nucleus ; and the regular appearance, about the 13th of November and the 1 1th of August, of shoot- ing stars, which probably form part of a belt of asteroids, in- tersecting the earth's orbit, and moving with planetary ve- locity.

Descending from the celestial regions to the earth, we would fain inquire into the relations that exist between the oscillations of the pendulum in air (the theory of which ha.s been perfected by Bessel) and the density of our planet ; and how the pendulum, acting the part of a plummet, can, to a certain extent, throw light upon the geological constitution of strata at great depths 1 By means of this instrument we are enabled to trace the striking analogy which exists be- tween the formation of the granular rocks composing the lava currents ejected from active volcanoes, and those endog- enous misses of granite, porphyry, and serpentine, which, is- suing from the interior of the earth, have broken, as erup- tive rocks, through the secondary strata, and modified them by contact, either in rendering them harder by the introduc- tion of silex, or reducing them into dolomite, or, finally, by inducing within them the formation of crystals of the most varied composition. The elevation of sporadic islands, of ,

INTKODUCTtON. 45

domes of trachyte, and cones of basalt, by the elastic forces emanating from the fluid interior of our globe, has led one of the first geologists of the age, Leopold von Buch, to the theory of the elevation of continents, and of mountain chains generally. This action of subterranean forces in breaking through and elevating strata of sedimentary rocks, of which the coast of Chili, in consequence of a great earthquake, fur- nished a recent example, leads to the assumption that the pelagic shells found by M. Bonpland and myself on the ridge of the Andes, at an elevation of more than 15,000 English feet, may have been conveyed to so extraordinary a position, not by a rising of the ocean, but by the agency of volcanic forces capable of elevating into ridges the softened crust of the earth.

I apply the term volcanic^ in the widest sense of the word, to every action exercised by the interior of a planet on its external crust. The surface of our globe, and that of the moon, manifest traces of this action, which in the former, at least, has varied during the course of ages. Those who are ignorant of tlio fact that the internal heat of the earth in- creases so rapidly with the increase of depth that granite is m a state of fusion about twenty or thirty geographical miles below the surface,* can not have a clear conception of the causes, and the simultaneous occurrence of volcanic eruptions at places widely removed from one another, or of the extent and intersection of circles of commotion in earthquakes, or of the uniformity of temperature, and equality of chemical com- position observed in thermal springs during a long course of years. The quantity of heat peculiar to a planet is, however, a matter of such importance — being the result of its primitive condensation, and varying according to the nature and dura- tion of the radiation — that the study of this subject may throw some degree of light on the history of the atmosphere, and the distribution of the organic bodies imbedded in the solid crust of the earth. This study enables us to understand how a tropical temperature, independent of latitude (that is, of the distance from the poles), may have been produced by deep fissures remaining open, and exhaling heat from the in-

* The determinations usually given of the point of fusion are in general much too high for refracting substances. According to the very accurate researches of Mitscherlich, the melting point of granite can hardly exceed 2372° F.

[Dr. Mantell states in The Wonders of Geology, 1848, vol. i., p. 34, that this increase of temperature amounts to 1° of Fahrenheit for eveiy fifty-four feet of vertical depth,"} — Tr.

46 coSxMos.

terior of the globe, at a period when the earth's crust we^ still furrowed and rent, and only in a state of semi-solidifica- tion ; and a primordial condition is thus revealed to us, in which the temperature of the atmosphere, and climates gen- erally, were owing rather to a liberation of caloric and of dif- ferent gaseous emanations (that is to say, rather to the ener- getic reaction of the interior on the exterior) than to the posi- tion of the earth with respect to the central body, the sun.

The cold regions of the earth contain, deposited in sedi- mentary strata, the products of tropical climates ; thus, in the coal formations, we find the trunks of palms standing up- right amid coniferee, tree ferns, goniatites, and fishes having rhomboidal osseous scales ;* in the Jura limestone, colossal skeletons of crocodiles, plesiosauri, planulites, and stems of the cycadese ; in the chalk formations, small polythalamia and bryozoa, whose species still exist in our seas ; in tripoli, or polishing slate, in the semi-opal and the farina-like opal or mountain meal, agglomerations of siliceous infusoria, which have been brought to light by the powerful microscope of Ehrenberg;t and, lastly, in transported soils, and in certain caves, the bones of elephants, hyenas, and lions. An intimate acquaintance with the physical phenomena of the universe leads us to regard the products of warm latitudes that are thus found in a fossil condition in northern regions not merely as incentives to barren curiosity, but as subjects awakening deep reflection, and opening new sources of study.

The number and the variety of the objects I have alluded to give rise to the question whether general considerations of physical phenomena can be made sufficiently clear to persons who have not acquired a detailed and special knowledge of

* See the classical woik on the fislies of the Old World by Agassiz, Reck, sur les Poissons Fossiles, 1834, vol. i., p. 38; vol. ii., p. 3, 28, 34, App., p. 6. The whole genus of Amblypterus, Ag., nearly allied to Palaeouiscus (called also Palueothrissum), lies buried beneath the Jura formations in the old carboniferous strata. Scales which, in some fishes, as in the family of Lepidoides (ordei* of Ganoides), are formed like teeth, and covered in certain pai'ts with enamel, belong, after the Placoides, to the oldest forms of fossil fishes ; their living representa- tives are still found in two genera, the Bichir of the Nile and Senegal, and the Lepidosteus of the Ohio.

\ [The polishing slate of Bilin is stated by M. Ehrenberg to form a series of strata fourteen feet in thickness, entirely made up of the sili- ceous shells of GaillonellcB, of such extreme minuteness that a cubic inch of the stone contains forty-one thousand millions ! The Bergmehl (mountain meal ov fossil farina) of San Flora, in Tuscany, is one mass of auimalculites. See the interesting work of G. A Manlell, On Ik^f Medals of Creation, vol. i., p. 223.]— jTr.

INTRODUCTJOX. 47

descriptive natural history, geology, or mathematical astron- omy ? I think we ought to distinguish here between him whose task it is to collect the individual details of" various observations, and study the mutual relations existing among them, and him to whom these relations are to be revealed, under the form of general results. The former should be aT5- quainted with the specialities of phenomena, that he may ar- rive at a generalization of ideas as the result, at least in part, of his own observations, experiments, and calculations. It can not be denied, that where there is an absence of positive knowledge of physical phenomena, the general results which impart so great a charm to the study of nature can not all be made equally clear and intelligible to the reader, but still I venture to hope, that in the work which I am now prepar- ing on the physical laws of the universe, the greater part of the facts advanced can be made manifest without the neces- sity of appealing to fundamental views and principles. The picture of nature thus drawn, notmthstanding the want of distinctness of some of its outlines, will not be the less able to enrich the intellect, enlarge the sphere of ideas, and nourish and vivify the imagiuation.

There is, perhaps, some truth in the accusation advanced against many German scientific works, that they 'lessen the value of general views by an accumulation of detail, and do not sufficiently distinguish between those great results which form, as it were, the beacon lights of science, and the long series of means by which they have been attained. This method of treating scientific subjects led the most illustrious of our poets* to exclaim with impatience, " The Germans have the art of making science inaccessible." An edifice can not produce a striking efTect until the scaffolding is removed, that had of necessity been used during its erection. Thus the uniformity of figure observed in the distribution of continental masses, which all terminate toward the south in a pyramidal form, and expand toward the north (a law that determines the nature of climates, the direction of currents in the ocean and the atmosphere, and the transition of certain types of tropical vegetation toward the southern temperate zone), may be clearly apprehended without any knowledge of the geo- desical and astronomical operations by means of which these pyramidal forms of continents have been determiued. In like manner, physical geography teaches us by how many leagues

* Gotlie, iu Die Aphorismen ilbcr NaturwisscJischaft, bd. I., .s, 155 ( Werke kleine Ausgabe, von 1833.)

48 COSMOS.

the equatorial axis exceeds the polar axis of the globe, and shows us the mean equality of the flattening of the two hemi- spheres, without entaiUng on us the necessity of giving the detail of the measurement of the degrees in the meridian, or the observations on the pendulum, which have led us to know that the true figure of our globe is not exactly that of a regu- lar ellipsoid of revolution, and that this irregularity is reflect- ed in the corresponding irregularity of the movements of the moon.

The views of comparative geography have been specially enlarged by that admirable work, Erdkunde im Verhciltniss zur Natur und zur Geschichte, in which Carl Emitter so ably delineates the physiognomy of our globe, and shows the influ- ence of its external configuration on the physical phenomena on its surface, on the migrations, laws, and manners of nations, and on all the principal historical events enacted upon the face of the earth.

France possesses an immortal work, L' Exjoosition du Sijs- te?7ie dtc Monde, in which the author has combined the results of the highest astronomical and mathematical labors, and pre- sented them to his readers free from all processes of demon- stration. The structure of the heavens is here reduced to the simple solution of a great problem in mechanics ; yet Laplace's work has never yet been accused of incompleteness and want of profundity.

The distinction between dissimilar subjects, and the sepa- ration of the general from the special, are not only conducive to the attainment of perspicuity in the composition of a phys- i'-al history of the universe, but are also the means by which a character of greater elevation may be imparted to the study of nature. By the suppression of all unnecessary detail, the great masses are better seen, and the reasoning faculty is ena- bled to grasp all that might otherwise escape the limited range of the senses.

The exposition of general results has, it must be owned, been singularly facilitated by the happy revolution experienced since •he close of the last century, in the condition of all the special sciences, more particularly of geology, chemistry, and descrip- t.ive natural history. In proportion as laws admit of more .general application, and as sciences mutually enrich each other, md by their extension become connected together in more im- oierous and more intimate relations, the development of gen- eral truths may be given with conciseness devoid of superfici- ality. On being first examined, all phenomena appear to be

INTRODUCTION. 49

isolated, and it is only by the result of a multiplicity of obser- vations, combined by reason, that we are able to trace the mutual relations existing between them. If, however, in the present age, which is so strongly characterized by a brilliant course of scientific discoveries, we perceive a w-ant of connec- tion in the phenomena of certain sciences, we may anticipate the revelation of new facts, whose importance will probably be commensurate with the attention directed to these branches of study. Expectations of this nature may be entertained with regard to meteorology, several parts of optics, and to radiating heat, and electro-magnetism, since the admirable discoveries of Melloni and Faraday. A fertile field is here opened to dis- covery, although the voltaic pile has already taught us the intimate connection existing between electric, magnetic, and chemical phenomena. Who will venture to affirm that we have any precise knowledge, in the present day, of that part of the atmosphere which is not oxygen, or that thousands of gaseous substances affecting our organs may not be mixed with the nitrogen, or, finally, that we have even discovered the whole number of the forces which pervade the universe ?

It is not the purpose of this essay on the physical history of the world to reduce all sensible phenomena to a small number of abstract principles, based on reason only. The physical history of the universe, whose exposition I attempt to develop, does not pretend to rise to the perilous abstractions of a purely rational science of nature, and is simply a phydcal geography, combined icith a descrijotion of the regions of space and the bodies occujnjing them. Devoid of the profoundness of a purely speculative philosophy, my essay on the Cos^nos treats of the contemplation of the universe, and is based upon a rational empiricism, that is to say, upon the results of the facts regis- tered by science, and tested by the operations of the intellect. It is within these limits alone that the work, which I now venture to undertake, appertains to the sphere of labor to which I have devoted myself throughout the course of my long scientific career. The path of inquiry is not unknown to me, although it may be pursued by others with greater success. The unity which I seek to attain in the development of the great phenomena of the universe is analogous to that which historical composition is capable of acquiring. All points relating to the accidental individuahties, and the essen- tial variations of the actual, whether in the form and arrange- ment of natural objects in the struggle of man against the elements, or of nations against nations, do not admit of being

Vol. I— C

50 COSMOS.

based only on a rational foundation — that is to say, of being deduced from ideas alone.

It seems to me that a like degree of empiricism attaches to the Description of the Universe and to Civil History ; but in reflecting upon physical phenomena and events, and tracing their causes by the process of reason, we become more and more convinced of the truth of the ancient doctrine, that the forces inherent in matter, and those which govel'n the moral world, exercise their action under the control of primordial necessity, and in accordance with movements occurring period- ically after longer or shorter intervals.

It is this necessity, this occult but permanent connection, this periodical recurrence in the progressive development of forms, phenomena, and events, which constitute nature, obe- dient to the first impulse imparted to it. Physics, as the term signifies, is limited to the explanation of the phenomena of the material world by the properties of matter. The ultimate object of the experimental sciences is, therefore, to discover laws, and to trace their progressive generalization. All that exceeds this goes beyond the province of the physical descrip- tion of the universe, and appertains to a range of higher spec- ulative views.

Emanuel Kant, one of the few philosophers who have es- caped the imputation of impiety, has defined with rare sagac- ity the limits of physical explanations, in his celebrated essay On the Theory and Strncture of the Heaven?,, published at Konigsberg in 1755.

The study of a science that promises to lead us through the vast range of creation may be compared to a journey in a far- distant land. Before w^e set forth, we consider, and often with distrust, our own strength, and that of the guide we have chosen. But the apprehensions which have originated in the abundance and the difficulties attached to the subjects we would embrace, recede from view as we remember that with the increase of observations in the present day there has also arisen a more intimate knowledge of the connection existing among all phenomena. It has not unfrequently happened, that the researches made at remote distances have often and unexpectedly thrown light upon subjects which had long re- sisted the attempts made to explain them within the narrow limits of our own sphere of observation. Organic forms tliat had long remained isolated, both in the animal and vegetable kingdom, have been connected by the discovery of intermediate links or stages of transition. The geography of beings endov/

INTRODUCTION. 51

ed with life attains completeness as we see the species, genera, and entire families belonging to one hemisphere, reflected, as it were, in analogous animal and vegetable forms in the oppo- site liemisphere. These are, so to speak, the equivalents w^hich mutually personate and replace one another in the great series of organisms. These connecting links and stages of transition may be traced, alternately, in a deficiency or an excess of de- velopment of certain parts, in the mode of junction of distinct organs, in the differences in the balance of forces, or in a re- semblance to intermediate forms which are not permanent, but merely characteristic of certain phases of normal devel- opment. Passing from the consideration of beings endowed with life to that of inorganic bodies, we find many striking illustrations of the high state of advancement to which modern geology has attained. We thus see, according to the grand views of Elie de Beaumont, how chains of mountains dividing different climates and floras and different races of men, reveal to us their relative age, both by the character of the sediment- ary strata they have uplifted, and by the directions which they follow over the long fissures with which the earth's crust is furrowed. Relations of superposition of trachyte and of syenitic porphyry, of diorite and of serpentine, which remuin doubtful when considered in the auriferous soil of Hungary, in the rich platinum districts of the Oural, and on the south- western declivity of the Siberian Altai, are elucidated by the observations that have been made on the plateaux of Mexico and Antioquia, and in the unhealthy ravines of Choco. The most important facts on which the physical history of the world has been based in modern times, have not been accu- mulated by chance. It has at length been fully acknowledg- ed, and the conviction is characteristic of the age, that the narratives of distant travels, too long occupied in the mere recital of hazardous adventures, can only be made a source of instruction where the traveler is acquainted with the condi- tion of the science he would enlarge, and is guided by reason in his researches.

It is by this tendency to generalization, which is only dan- gerous in its abuse, that a great portion of the physical knowl- edge already acquired may be made the common property of all classes of society ; but, in order to render the instruction imparted by these means commensurate with the importance of the subject, it is desirable to deviate as widely as possible from the imperfect compilations designated, till the close of the eighteenth century, by t^e inappropriate term of popula?

52 cosjMos.

knowledge. I take pleasure in persuading myself that scien- tific subjects may be treated of in language at once dignified, grave, and animated, and that those who are restricted with- in the circumscribed limits of ordinary life, and have long re- mained strangers to an intimate communion with nature, may thus have opened to them one of the richest sources of enjoyment, by which the mind is invigorated by the acquisi- tion of new ideas. Communion with nature awakens within us perceptive faculties that bad long lain dormant ; and we thus comprehend at a single glance the influence exercised by physical discoveries on the enlargement of the sphere of intel- lect, and perceive how a judicious application of mechanics, chemistry, and other sciences may be made conducive to na- tional prosperity.

A more accurate knowledge of the connection of physical phenomena will also tend to remove the prevalent error that all branches of natural science are not equally important in relation to general cultivation and industrial progress. An arbitrary distinction is frequently made between the various degrees of importance appertaining to mathematical sciences, to the study of organized beings, the knowledge of electro-" magnetism, and investigations of the general properties of mat- ter in its different conditions of molecular aggregation ; and it is not uncommon presumptuously to affix a supposed stigma upon researches of this nature, by terming them " purely the- oretical," forgetting, although the fact has been long attested, that in the observation of a phenomenon, which at first sight appears to be wholly isolated, may be concealed the germ of a great discovery. When Aloysio Galvani first stimulated the nervous fiber by the accidental contact of two heterogeneous metals, his cotemporaries could never have anticipated that the action of the voltaic pile would discover to us, in the al- kalies, metals of a silvery luster, so light as to swim on wa- ter, and eminently inflammable ; or that it would become a powerful instrument of chemical analysis, and at the same time a thermoscope and a magnet. When Huygens first ob- served, in 1678, the phenomenon of the polarization of light, exhibited in the difference between the two rays into which a pencil of light divides itself in passing through a doubly refracting crystal, it could not have been foreseen that, a century and a half later, the great philosopher Arago would, by his discovery of chromatic ijolarization, be led to discern, by means of a small fragment of Iceland spar, whether solar light emanates from a solid body or a gaseous covering, oi

INTRODUCTION. 53

whether comets transmit light directly or merely by reflec- tion.*

An equal appreciation of all branches of the mathematical^ physical, and natural sciences is a special requirement of the present age, in which the material wealth and the growing prosperity of nations are principally based upon a more en- lightened employment of the products and forces of nature. The most superficial glance at the present condition of Europe shows that a diminution, or even a total annihilation of na- tional prosperity, must be the award of those states who shrink with slothful indifierence from the great struggle of rival na- tions in the career of the industrial arts. It is with nations as with nature, which, according to a happy expression of G6the,t " knows no pause in progress and development, and attaches her curse on all inaction." The propagation of an earnest and sound knowledge of science can therefore alone avert the dangers of which I have spoken. Man can not act upon nature, or appropriate her forces to his own use, without comprehending their full extent, and having an intimate ac- quaintance with the laws of the physical world. Bacon has said that, in human societies, knowledge is power. Both must rise and sink together. But the knowledge that results from the free action of thought is at once the delight and the in- destructible prerogative of man ; and in forming part of the wealth of mankind, it not unfrequently serves as a substitute for the natural riches, which are but spariiigly scattered over the earth. Those states which take no active part in the general industrial movement, in the choice and preparation of natural substances, or in the application of mechanics and chemistry, and among whom this activity is not appreciated by all classes of society, will infallibly see their prosperity di- minish in proportion as neighboring countries become strength- ened and invigorated under the genial influence of arts and sciences.

As in nobler spheres of thought and sentiment, in philosophy, poetry, and the fine arts, the object at which we aim ought to be an inwaid one — an ennoblement of the intellect — so ought we likevidse, in our pursuit of science, to strive after a knowl- edge of the laws and the principles of unity that pervade the vital forces of the universe ; and it is by such a course that

* Ai'ago's Discoveries ia the year 1811. — Delambre's Histoire de V Ait., p. 652. (Passage already quoted.)

t Gothe, ill Die AphoHsmen uber Naturwissenschaft. — Werke, bd. 1... B. 4

54 COSMOS.

physical studies may be made subservient to the progress of in- dustry, which is a conquest of mind over matter. By a hap- py connection of causes and effects, we often see the useful link- ed to the beautiful and the exalted. The improvement of agri- culture in the hands of freemen, and on properties of a mod- erate extent — the flourishing state of the mechanical arts freed from the trammels of municipal restrictions — the increased impetus imparted to commerce by the multiplied means of contact of nations v^^ith each other, are all brilliant results of the intellectual progress of mankind, and of the amelioration of political institutions, in which this progress is reflected. The picture presented by modern history ought to convince those who are tardy in awakening to the truth of the lesson it teaches.

Nor let it be feared that the marked predilection for the study of nature, and for industrial progress, which is so char- acteristic of the present age, should necessarily have a tenden- cy to retard the noble exertions of the intellect in the domains of philosophy, classical history, and antiquity, or to deprive the arts by which life is embellished of the vivifying breath of imagination. Where all the germs of civilization are devel- oped beneath the ff^gis of free institutions and wise legislation, there is no cause for apprehending that any one branch of knowledge should be cultivated to the prejudice of others. All afford the state precious fruits, whether they yield nourish- ment to man and constitute his physical wealth, or whether, more permanent in their nature, they transmit in the works of mind the glory of nations to remotest posterity. The Spar- tans, notwithstanding their Doric austerity, prayed the gods to grant them " the beautiful with the good."*

I will no longer dwell upon the considerations of the influ- ence exercised by the mathematical and physical sciences on all that appertains to the material wants of social life, for the vast extent of the course on which I am entering forbids me to insist further upon the utility of these applications. Ac- customed to distant excursions, I may, perhaps, have erred in describing the path before us as more smooth and pleasant than it really is, for such is wont to be the practice of those who delight in guiding others to the summits of lofty mount- ains : they praise the view even when great part of the dis- tant plains lie hidden by clouds, knowing that this half-trans- parent vapory vail imparts to the scene a certain charm from

* Pseudo-Plato. — Alcib., xi., p. 184, ed. Steph. ; Plut., Instituta La- conica, p. 253, ed. Hutten.

, j\TKoDi;( rrox. oa

the power exercised by the imagination over the domani of the senses. In like manner, from the height occupied by the phys- ical history of the world, all parts of the horizon will not ap- pear equally clear and well defined. This indistinctness will not, however, be wholly owing to the present imperfect state of some of the sciences, but in part, likewise, to the unskill- fulness of the guide who has imprudently ventured to ascend these lofty summits.

The object of this introductory notice is not, however, solely to draw attention to the importance and greatness of the phys- ical history of the universe, for in the present day these are too well understood to be contested, but likewise to prove how, without detriment to the stability of special studies, we may be enabled to generalize our ideas by concentrating them in one conmion focus, and thus arrive at a point of view from w^hich all the organisms and forces of nature may be seen as one Hving, active whole, animated by one sole impulse, " Na- ture," as Schelling remarks in his poetic discourse on art, "is not an inert mass ; and to him who can comprehend her vast sublimity, she reveals herself as the creative force of the uni- verse— before all time, eternal, ever active, she calls to life all things, whether perishable or imperishable."

By uniting, under one point of view, both the phenomena of our own globe and those presented in the regions of space, we embrace the limits of the science of the Cosmos, and con- vert the physical history of the globe into the physical history of the universe, the one term being modeled upon that of the other. This science of the Cosmos is not, however, to be re- garded as a. mere encyclopedic aggregation of the most im- portant and general results that have been collected together from special branches of knowledge. These results are noth- ing more than the materials for a vast edifice, and their com- bination can not constitute the physical history of the w^orld, whose exalted part it is to show the simultaneous action and the connecting links of the forces which pervade the universe. The distribution of organic types in different climates and at different elevations — that is to say, the geography of plants and animals — differs as widely from botany and descriptive zoology as geology does from mineralogy, properly so called. The physical history of the universe must not, therefore, be confounded with the Encyclopedias of the Natural Sciences, as they have hitherto been compiled, and whose title is as vao-ue as their limits are ill defined. In the work before us, partial facts will be considered only in relation to the whole

5(j COSMOS.

The higher the point of view, the greater is the nece*,sity lor a systematic mode of treating the subject in language at once animated and picturesque.

But thought and language have ever been most intimately allied. If langiiage, by its originality of structure and its native richness, can, in its delineations, interpret thought M^ith grace and clearness, and if, by its happy flexibility, it can paint with vivid truthfulness the objects of the external world, it reacts at the same time upon thought, and animates it, as it were, with the breath of life. It is this mutual reaction which makes words more than mere signs and forms of thought ; and the beneficent influence of a language is most strikingly man- ifested on its native soil, where it has sprung spontaneously from the minds of the people, whose character it embodies. Proud of a country that seeks to concentrate her strength in intellectual unity, the writer recalls with delight the advant- ages he has enjoyed in being permitted to express his thoughts in his native language ; and truly happy is he who, in at- tempting to give a lucid exposition of the great phenomena of the universe, is able to draw from the depths of a language, which, through the free exercise of thought, and by the efiii- sions of creative fancy, has for centuries past exercised so pow- erful an influence over the destinies of man.

M.MITS AND METHOD OF EXPOSITION OF THE PHYSICAL DESCRIPTION

OF THE UNIVERSE.

I HAVE endeavored, in the preceding part of my work, to explain and illustrate, by various examples, how the enjoy- ments presented by the aspect of nature, varying as they do in the sources from whence they flow, may be multiplied and ennobled by an acquaintance with the connection of phenom- ena and the laws by which they are regulated. It remains, then, for me to examine the spirit of the method in which the exposition of the physical descriiJtion of the utiiverse should be conducted, and to indicate the limits of this science in ac- cordance with the views I have acquired in the course of my studies and travels in various parts of the earth. I trust I may flatter myself with a hope that a treatise of this nature will justify the title I have ventured to adopt for my work, and exonerate me from the reproach of a presumption that would be doubly reprehensible in a scientific discussion.

Before entering upon the delineation of the partial phenom-

INTRODUCTION. 57

ena which are found to be distributed in various g^roups, I would consider a few general questions intimately connected together, and bearing upon the nature of our kno^vledge of the external world and its different relations, in all epochs of history and in all phases of intellectual advancement. Under this head will be comprised the following considerations :

1 . The precise limits of the physical description of the uni- verse, considered as a distinct science.

2. A brief enumeration of the totality of natural phenomena, presented under the form of a general delineatioii of nature.

3. The influence of the external world on the imagination and feelings, which has acted in modern times as a powerful impulse toward the study of natural science, by giving anima- tion to the description of distant regions and to the delineation of natural scenery, as far as it is characterized by vegetable physiognomy and by the cultivation of exotic plants, and their arrangement in well- contrasted groups.

4. The history of the contemplation of nature, or the pro- gressive development of the idea of the Cosmos, considered with reference to the historical and geographical facts that have led to the discovery of the connection of phenomena.

The higher the point of view from which natural phenome- na may be considered, the more necessary it is to circumscribe the science within its just limits, and to distinguish it from all other analogous or auxiliary studies.

Physical cosmography is founded on the contemplation of all created things-:-all that exists in space, whether as substances or forces — that is, all the material beings that constitute the universe. The science which I would attempt to define pre- sents itself, therefore, to man, as the inhabitant of the earth, under a two-fold form — as the earth itself and the reo-ions of space. It is with a view of showing the actual character and the independence of the study of physical cosmography, and at the saraie time indicating the nature of its relations to general fhysics, descrij)tive natural history, geology, and comparative geography, that I will pause for a few moments to consider that portion of the science of the Cosmos which concerns the earth. As the history of philosophy does not consist of a mere material enumeration of the philosophical views entertained in different ages, neither should the physical description of the universe be a simple encyclopedic compilation of the sciences we have enumerated. The difficulty of defining the limits of intimately-connected studies has been increased, because for centuries it has been customary to designate various branches

C2

58 COSMOS.

of empirical knowledge by terms which admit either ot too wide or too limited a definition of the ideas which they were intended to convey, and arc, besides, objectionable from hav- ing had a different signification in those classical languages of antiquity from which they have been borrowed. The terms physiology, physics, natural history, geology, and geography arose, and were commonly used, long before clear ideas were entertained of the diversity of objects embraced by these sciences, and consequently of their reciprocal limitation. Such is the influence of long habit upon language, that by one of the nations of Europe most advanced in civilization the word " physic" is applied to medicine, while in a society of justly deserved universal reputation, technical chemistry, geology, and astronomy (purely experimental sciences) are comprised under the head of" Philosophical Transactions."

An attempt has often been made, and almost always in vain, to substitute new and more appropriate terms for these ancient designations, which, notwithstanding their undoubted vague- ness, are now generally understood. These changes have been proposed, for the most part, by those who have occupied them- selves with the general classification of the various branches of knowledge, from the first appearance of the great encyclo- pedia [Margarita Pliilosophica) of Gregory Reisch,* prior of the Chartreuse at Freiburg, toward the close of the fifteenth century, to Lord Bacon, and from Bacon to D'Alembert ; and in recent times to an eminent physicist, Andre Marie Ampere. t

* The Margarita PhilosopJiica of Gregory Reisch, prior of the Char- treuse at Freiburg, first appeared under the following title : Epitome omnis Philosophice, alias Margarita PhilosopJiica, tractans de omni generi scibili. The Heidelberg edition (1486), and that of Strasburg (1504), both bear this title, but the first part was suppi'essed in the Freiburg edition of the same year, as well as in the twelve subsequent editions, vvhich succeeded one another, at short intervals, till 1.535. This work exercised a great influence on the ditfusion of mathematical and physic- al sciences toward the beginning of the sixteenth century, and CLas^es, the learned author of L'Apercu Historique des Methodes en GeomHrtc (1837), has shown the great importance of Reisch's Encyclopedia in the history of mathematics in the Middle Ages. I have had recourse to a passage in the Margarita PhilosopTiica, found only in the edition of 1513, to elucidate the important question of the relations between the statements of the geographer of Saint-Die, Hylacomilus (Martin VValdseemiiller), the first who gave the name of America to the New Continent, and those of Amerigo Vespucci, Rene, King of Jerusalem and Duke of Lorraine, as also those contained in the celebrated editions of Ptolemy of 1513 and 1522. See my Examen Critique de la G^o- grapkip. du Nouveau Continent, et des Progres de V Astronomie Nautiqtie aux 15e et 16e Siecles, t. iv., p. 99-125.

t Ampere, Essai sn.r la Phil, des Sciences, 1834, p. 25. Whewell,

IXTHODITTroW 59

The selection of an inappropriate Greek nomenclature has per- haps been even more prejudicial to the last of these attempts than the injudicious use of binary divisions and the excessive multiplication of groups.

The physical description of the world, considering the uni- verse as an object of the external senses, does undoubtedly re- quire the aid of general physics and of descriptive natural histo- ly, but the contemplation of all created thmgs, which are hnked together, and form one luhole, animated by internal forces, gives to the science we are considering a peculiar character. Phys- ical science considers only the general properties of bodies ; it is the product of abstraction — a generalization of perceptible phenomena ; and even in the work in which were laid the first foundations of general physics, in the eight books on physics of Aristotle,* all the phenomena of nature are consid- ered as depending upon the primitive and vital action of one sole force, from which emanate all the movements of the uni- verse. The terrestrial portion of physical cosmography, for which I would willingly retain the expressive designation of 'physical geograjjhij, treats of the distribution of magnetism in our planet with relation to its intensity and direction, but does not enter into a consideration of the laws of attraction or re- pulsion of the poles, or the means of eliciting either permanent or transitory electro-magnetic currents. Physical geography depicts in broad outlines the even or irregular configuration of continents, the relations of superficial area, and the distribution of continental masses in the two hemispheres, a distribution which exercises a powerful influence on the diversity of climate and the meteorological modifications of the atmosphere ; this science defines the character of mountain chains, which, hav- ing been elevated at different epochs, constitute distinct sys- tems, whether they run in parallel lines or intersect one an- other ; determines the mean height of continents above the level of the sea, the position of the center of gravity of their volume, and the relation of the highest summits of mountain chains to the mean elevation of their crests, or to their prox- imity with the sea-shore. It depicts the eruptive rocks as principles of movement, acting upon the sedimentary rocks by traversing, uplifting, and inchning them at various angles ; it

Philosophy of the Inductive Sciences, volt ii., p. 277. Park, Pantoiogy^

* All changes in the physical world may be reduced to motion. Aristot., Phys. Ansc, iii., 1 and 4, p. 200, 201. Bekker, viii., 1, 8, and 9, p. 250, 262, 265. De Genere et Corr., ii., 10, p. 336. Psendo-Aris- tot., De Mundo. cap. vi., p. 398.

.«|HX^

60 COSMOS.

considers volcanoes either as isolated, or ranged in single or in double series, and extending their sphere of action to various distances, either by raising long and narrow lines of rocks, or by means of circles of commotion, which expand or diminish in diameter in the course of ages. This terrestrial portion ot the science of the Cosmos describes the strife of the liquid ele- ment with the solid land ; it indicates the features possessed in common by all great rivers in the upper and lower portion of their course, and in their mode of bifurcation when their basins are unclosed ; and shows us rivers breaking through the highest mountain chains, or following for a long time a course parallel to them, either at their base, or at a consider- able distance, Avhere the elevation of the strata of the mount- ain system and the direction of their inclination correspond to the configuration of the table-land. It is only the general results of comparative orography and hydrography that belong to the science whose true limits I am desirous of determining, and not the special enumeration of the greatest elevations of our globe, of active volcanoes, of rivers, and the number of their tributaries, these details falling rather within the domain of geography, properly so called. We would here only con- sider phenomena in their mutual connection, and in their re- lations to different zones of our planet, and to its physical con- stitution generally. The specialities both of inorganic and or- ganized matter, classed according to analogy of form and com- position, undoubtedly constitute a most interesting branch of study, but they appertain to a sphere of ideas having no affin- ity with the subject of this work.

The description of different countries certainly furnishes us with the most important materials for the composition of a physical geography ; but the combination of these differenl descriptions, ranged in series, would as little give us a tru« image of the general conformation of the irregular surface of our globe, as a succession of all the floras of different region? would constitute that M^iich I designate as a Geogra2)hy of Plants. It is by subjecting isolated observations to the process of thought, and by combining and comparing them, that we are enabled to discover the relations existing in common be tween the climatic distribution of beings and the individualitj of organic forms (in the morphology or descriptive natural his- tory of plants and animals) ; and it is by induction that we are led to comprehend numerical laws, the proportion of nat- ural families to the whole number of species, and to desig-nate the latitude or geographical position of the zones in whose

INTRODUCTION. 61

plains each org:anic form attains the maximum of its develop- ment. Considerations of this nature, by their tendency to generalization, impress a nobler character on the physical de- scription of the globe, and enable us to undfrstand how the aspect of the scenery, that is to say, the impression produced upon the mind by the physiognomy of the vegetation, depends upon the local distribution, the number, and the luxuriance of growth of the vegetable forms predominating in the general mass. The catalogues of organized beings, to which was for- merly given the pompous title of Systems of Nature, present us with an admirably connected arrangement by analogies of structure, either in the perfected development of these beings, or in the different phases which, in accordance with the views of a spiral evolution, affect in vegetables the leaves, bracts, calyx, corolla, and fructifying organs ; and in animals, with more or less symmetrical regularity, the cellular and fibrous tissues, and their perfect or but obscurely developed articula- tions. But these pretended systems of nature, however ingen- ious their mode of classification may be, do not show us or- ganic beings as they are distributed in groups throughout our planet, according to their difierent relations of latitude and elevation above the level of the sea, and to climatic influences, which are owing to general and often very remote causes. The ultimate aim of physical geography is, however, as we have already said, to recognize unity in the vast diversity of phenomena, and by the exercise of thought and the combina- tion of observations, to discern the constancy of phenomena in the midst of apparent changes. In the exposition of the terrestrial portion of the Cosmos, it will occasionally be neces- sary to descend to veiy special facts ; but this will only be in order to recall the connection existing betM^een the actual dis- tribution of organic beings over the globe, and the laws of the ideal classification by natural families, analogy of internal or- ganization, and progressive evolution.

It follows from these discussions on the limits of the various sciences, and more particularly from the distinction which must necessarily be made between descriptive botany (morphology of vegetables) and the geography of plants, that in the phys ical history of the globe, the innumerable multitude of organ- ized bodies which embellish creation are considered rather ac- cording to zones of habitation or stations, and to differently inflected isothermal bands, than with reference to the princi- ples of gradation in the development of internal organism. Notwithstanding this, botany and zoology, which constitute

62 COSMOS.

the descriptive natural history of all organized beings, are the fruitful sources whence we draw the materials necessary to give a solid basis to the study of the mutual relations and connection of phenomena.

We will here subjoin one important observation by way of elucidating the connection of which we have spoken. The first general glance over the vegetation of a vast extent of a continent shows us forms the most dissimilar — Graminese and Orchideee, Coniferse and oaks, in local approximation to one another ; while natural families and genera, instead of being locally associated, are dispersed as if by chance. This disper- sion is, however, only apparent. The physical description of the globe teaches us that vegetation every where presents nu- merically constant relations in the development of its forms and types ; that in the same climates, the species which are wanting in one country are replaced in a neighboring one by other species of the same family ; and that this laiv of substi- tution, which seems to depend upon some inherent mysteries of the organism, considered with reference to its origin, main- tains in contiguous regions a numerical relation between the species of various great families and the general mass of the phanerogamic plants constituting the two floras. We thus find a principle of unity and a primitive plan of distribution revealed in the multiplicity of the distinct organizations by which these regions are occupied ; and we also discover in each zone, and diversified according to the families of plants, a slow but continuous action on the aerial ocean, depending upon the influence of light — the primary condition of all or- ganic vitality — on the solid and liquid surface of our planet. It might be said, in accordance with a beautiful expression of Lavoisier, that the ancient marvel of the myth of Prometheus was incessantly renewed before our eyes.

If we extend the course which we have proposed, following in the exposition of the physical description of the earth to the sidereal part of the science of the Cosmos, the delineation of the regions of space and the bodies by which they are occupied, we shall find our task simplified in no common degree. If, ac- cording to ancient but unphilosophical forms of nomenclature, we would distinguish between physics, that is to say, general considerations on the essence of matter, and the forces by which it is actuated, and chemistry, which treats of the nature of substances, their elementary composition, and those attrac- tions that are not determined solely by the relations of mass, we must admit that the description of the earth comprises at

INTRODUCTION. (53

once physical and chejiiical actions. In addition to gravita- tion, which must be considered as a primitive force in nature, we observe that attractions of another kind are at work around us, both in the interior of our planet and on its surface. These forces, to which we apply the term chemical ajjinity, act upon molecules in contact, or at infinitely minute distances from one another,* and which, being differently modified by electricity, heat, condensation in porous bodies, or by the contact of an intermediate substance, animate equally the inorganic world and animal and vegetable tissues. If we except the small asteroids, which appear to us under the forms of aerolites and shooting stars, the regions of space have hitherto presented to our direct observation physical phenomena alone ; and in the case of these, we know only with certainty the effects depend- ing upon the quantitative relations of matter or the distribu- tion of masses. The phenomena of the regions of space may consequently be considered as influenced by simple dynamical laws — the laws of motion.

The effects that may arise from the specific difference and the heteroofeneous nature of matter have not hitherto entered into our calculations of the mechanism of the heavens. The only means by which the inhabitants of our planet can enter into relation with the matter contained within the regions of space, whether existing in scattered forms or united into large spheroids, is by the phenomena of light, the propagation of luminous waves, and by the influence universally exercised by the force of gravitation or the attraction of masses. The ex- istence of a periodical action of the sun and moon on the va- riations of terrestrial magnetism is even at the present day extremely problematical. We have no direct experimental knowdedge regarding the properties and specific qualities of the masses circulating in space, or of the matter of w^hich they are probably composed, if we except what may be derived from the fall of aerolites or meteoric stones, wdiich, as we have al- ready observed, enter within the limits of our terrestrial sphere. It will be sufficient here to remark, that the direction and the excessive velocity of projection (a velocity wholly planetary) manifested by these masses, render it more than probable that

* On the question already discussed by Newton, regarding the differ- ence existing between the atti-action of masses and molecular attraction, see Laplace, Exposition du Systeme du Monde, p. 384, and supplement to book X. of the Mecanique Celeste, p, 3, 4 ; Kant, Metaph. AnfangR. grunde der Naturwissenschaft, Sam. Werke, 1839, bd. v., s. 309 (Meta- physical Principles of the Natural Sciences) ; Pectet, Physique, 1838- vol, i., p. 59-63.

64 COSMOS.

they are small celestial bodies, which, being attracted by out planet, are made to deviate from their original course, and thus reach the earth enveloped in vapors, and in a high state of actual incandescence. The familiar aspect of these asteroids, and the analogies which they present with the minerals com- posing the earth's crust, undoubtedly afford ample grounds for surprise ;* but, in my opinion, the only conclusion to be drawn from these facts is, that, in general, planets and other sidereal masses, which, by the influence of a central body, have been agglomerated into rings of vapor, and subsequently into sphe- roids, being integrant parts of the same system, and having one common origin, may likewise be composed of substances chemically identical. Again, experiments with the pendulum, particularly those prosecuted with such rare precision by Bes- sel, confirm the Newtonian axiom, that bodies the most hete- rogeneous in their nature (as water, gold, quartz, granular limestone, and diflerent masses of aerolites) experience a per- fectly similar degree of acceleration from the attraction of the earth. To the experiments of the pendulum may be added the proofs furnished by purely astronomical observations. The almost perfect identity of the mass of Jupiter, deduced from the influence exercised by this stupendous planet on its own satel- lites, on Encke's comet of short period, and on the small planets Vesta, Juno, Ceres, and Pallas, indicates with equal certain- ty that within the limits of actual observation attraction is determined solely by the quantity of matter. t

This absence of any perceptible difierence in the nature of matter, alike proved by direct observation and theoretical de- ductions, imparts a high degree of simplicity to the mechanism of the heavens. The immeasurable extent of the regions of space being subjected to laws of motion alone, the sidereal portion of the science of the Cosmos is based on the pure and abundant source of mathematical astronomy, as is the terres- trial portion on physics, chemistry, and organic morphology ; but the domain of these three last-named sciences embraces

* [The analysis of an aeroHte which fell a few years since in Mary land. United States, and was examined by Professor Silliman, of New Haven, Connecticut, gave the following results: Oxyd of iron, 24 ; ox- yd of nickel, 1*25 ; silica, with earthy matter, 3*46 ; sulphur, a trace =28-71. Dr. Mantell's Wonders of Geology, 1848, vol. i.. p. 51.]— 7V.

t Poisson, Connaissances des Temps pour V Annee 1836, p. (j4-6(). Bessel, Poggeudorf 's Annalen, bd. xxv., s. 417. Encke, Abhandhingen der Berliner Academie (Trans, of the Berlin Academy), 1826, s. 257. Mitscherlich, Lehrbuck der Chemie (Manual of Chemistry), 1837 bd. i. 8. 352.

INTRODUCTION. 65

the consideration of phenomena which are so complicated, and have, up to the present time, been found so little suscep- tible of the application of rigorous method, that tht) physical science of the earth can not boast of the same certainty and simplicity in the exposition of facts and their mutual connec- tion which characterize the celestial portion of the Cosmos. It is not improbable that the difference to which we allude may furnish an explanation of the cause which, in the earliest ages of intellectual culture among the Greeks, directed the natural philosophy of the Pythagoreans with more ardor to the heavenly bodies and the regions of space than to the earth and its productions, and how through Philolaiis, and subse- quently through the analogous views of Aristarchus of Samos, and of Seleucus of Erythrea, this science has been made more conducive to the attainment of a knowledge of the true system of the world than the natural philosophy of the Ionian school could ever be to the physical history of the earth. Giving but little attention to the properties and specific differences of matter filling space, the great Italian school, in its Doric gravity, turned by preference toward all that relates to meas- ure, to the form of bodies, and to the number and distances of the planets,*" while the Ionian physicists directed their atten tion to the qualities of matter, its true or supposed metamor phoses, and to relations of origin. It was reserved for the powerful genius of Aristotle, alike profoundly speculative and practical, to sound with equal success the depths of abstraction and the inexhaustible resources of vital activity pervading the material world.

Several highly distinguished treatises on physical geography are prefaced by an introduction, whose purely astronomical sections are directed to the consideration of the earth in its planetary dependence, and as constituting a part of that great system which is animated by one central body, the sun. This course is diametrically opposed to the one which I propose following. In order adequately to estimate the dignity of the Cosmos, it is requisite that the sidereal portion, termed by Kant the oiaturaL history of the heavens, should not be made subordinate to the terrestrial. In the science of the Cosmos, according to the expression of Aristarchus of Samos, the pio- neer cf •the Copernican system, the sun, with its satellites, was nothing more than one of the innumerable stars by which space is occupied. The physical history of the world must, therefore, begin with the description of the heavenly bodies, * Compare Otfried MUller's Dorien, bd. i., s. 365.

■U6 ^ COSMOS.

and with a geographical sketch of the universe, or, I would rather say, a true map of the ivorld, such as was traced by the bold hand of the elder Herschel. If, notwithstanding the sraallness of our planet, the most considerable space and the most attentive consideration be here afforded to that which exclusively concerns it, this arises solely from the disproportion in the extent of our knowledge of that which is accessible and of that which is closed to our observation. This subordina- tion of the celestial to the terrestrial portion is met with in the great work of Bernard Varenius,'* w^hich appeared in the mid-

* Geographia Generalis iii qua affectiones generales telluris expli- cantur. The oldest Elzevir edition bears date 1650, the second 1672, and the third 1681 ; these were published at Cambridge, under New- ton's supervision. This excellent work by Varenius is, in the true sense of the words, a physical description of the earth. Since the work Hlstoria Natural de las Indias, 1590, in which the Jesuit Joseph de Acosta sketched in so masterly a manner the delineation of the New Continent, questions relating to the physical history of the earth have never been considered with such admirable generality. Acosta is rich- er in original observations, while Varenius embraces a wider circle of ideas, since his sojourn in Holland, which was at that period the center of vast commercial relations, had brought him in contact with a great number of w^ell-informed travelers. Generalis sive Universalis Geo- graphia dicitJir qute tellurem in genere considerat atque affectiones ex' plicat, non^ habita particulariitm regionum ratione. The general de- scription of the earth by Varenius {Pars Ahsoluta, cap. i.-xxii.) maybe considered as a treatise of comparative geography, if we adopt the term used by the author h.\m?,e\i {Geographia Comparativa, cap.xxxiii.-xl.), although this must be understood in a limited acceptation. We may cite the following among the most remarkable passages of this book : the enumeration of the systems of mountains ; the examination of the relations existing between their directions and the general form of con- tinents (p. 66, 76, ed. Cantab., 1681); a list of extinct volcanoes, and such as were still in a state of activity ; the discussion of facts relative to the general distribution of islands and archipelagoes (p. 220) ; the depth of the ocean I'elatively to the height of neighboring coasts (p. 103) ; the uniformity of level observed in all open seas (p. 97) ; the depend- ence of currents on the prevailing winds; the unequal saltness of the sea; the configuration of shores (p. 139); the direction of the winds as the result of ditferences of temperature, &c. We may further instance the remarkable considerations of Varenius regarding the equinoctial current from east to west, to which he attributes the origin of the Gulf Stream, beginning at Cape St. Augustiu, and issuing forth between Cuba and Florida (p. 140). Nothing can be more accurate than his description of the current which skirts the western coast of Africa, be- tween Cape Verde and the island of Fernando Po in the Gulf of Guinea. Varenius explains the formation of sporadic islands by supposing them to be *' the raised bottom of the sea:" magna spirihium inclusorum vi, sicut aliquando monies e terra protttsos esse quidam scribunt (p. 225). The edition published by Newton in 1681 {auciior et emendatior) un^ fortunately contains no additions from this great authority; and there is not even mention made of the polar compression of the globe, al-

IXTIIODUCTIOX. 07

d\e of the seventeenth century. He was tlie first to distinguish between general a?id special geography, the former of which he subdivides into an absolute, or, properly speaking, terres- trial part, and a relative or planetary portion, according to the mode of considering our planet either with reference to its surface in its diliereiit zones, or to its relations to the sun and moon. It redounds to the glory of Varenius that his work on General and Comparative Geography should in so high a degree have arrested the attention, of Newton. The imper- fect state of many of the auxiliary sciences from which this . writer was obliged to draw his materials prevented his work from corresponduig to the greatness of the design, and it was reserved for the present age, and for my own country, to see the delineation of comparative geography, drawn in its full extent, and in all its relations with the history of man, by the skillful hand of Carl Ritter.*

The enumeration of the most important results of the as- tronomical and physical sciences which in the history of the Cosmos radiate toward one common focus, may perhaps, to a certain degree, justify the designation I have given to my work, and, considered within the circumscribed limits I have proposed to myself, the undertaking may be esteemed less ad- venturous than the title. The introduction of new terms, es- pecially with reference to the general results of a science which

- though the experiments on the pendulum by Richer had been made nine years prior to the appearance of the Cambridge edition. Newton's Principia Mathematica Philosojjhice Natnralis were not communicated in manuscript to tlie Royal Society until April, 1G80. Much uncer- tainty seems to prevail regarding the birth-place of Varenius. Ja;cher says it was England, while, according to La Biographie Universclle (b. xlvii., p. 495), he is stated to have been bom at Amsterdam; but it would appear, from the dedicatory address to the burgomaster ol that city (see his Geographia Comparativa), that both suppositions ai'e false. Varenius expressly says that lie had sought refuge in Amsterdam, *' because his native city had been burned and completely destroyed during a long war," words which appear to apply to the north of Ger- many, and to the devastations of the Thirty Years' War. In his dedica- tion of another work, Descriptio regni Japonic^ (Amst., 1649), to the Senate of Hamburgh, Varenius says that he prosecuted his elementary mathematical studies in the gymnasium of that city. There is, there- fore, every reason to believe that this admirable geographer was a native of Germany, and was probajjly born at Luneburg ( TFV/^e?i. Mem. Theol., 1685, p. 2142; Zedler, Universal Lexicon, vol. xlvi., 1745. p. 187).

* Carl Ritter's Erdkundeim VerhuUniss zur Naturund zvr Geschichte des Menschen, oder allgemeine vergleichende Geographic (Geojjraphy in relation to Nature and the History o' Man, or general Comparativo Geography).

68 COSMOS.

ought to be accessible to all, has always been greatly in oppo- sition to my own practice ; and whenever I have enlarged upon the established nomenclature, it has only been in the specialities of descriptive botany and zoology, where the in- troduction of hitherto unknown objects rendered new names necessary. The denominations of physical descriptions of the universe, or physical cosmography, which I use indiscrimin- ately, have been modeled upon those o{ physical descriptio?is of the earth, that is to say, physical geography, terms that have lonor heen in common use. Descartes, whose o^enius was one of the most powerful manifested in any age, has left us a few fragments of a great work, which he intended publishing under the title of Monde, and for which he had prepared him- self by special studies, including even that of human anatomy. The uncommon, but definite expression of the science of the Cosmos recalls to the mind of the inhabitant of the earth that we are treating of a more wddely-extended horizon — of the assemblage of all things with which space is filled, from the remotest nebula? to the climatic distribution of those delicate tissues of vegetable matter which spread a variegated cover- ins: over the surface of our rocks.

The influence of narrow-minded views peculiar to the ear- lier ages of civilization led in all languages to a confusion of ideas in the synonymic use of the words earth and tvorld, while the common expressions voyages round the ivorld, map of the ivorld, and neiu ivorld, afford further illustrations of the same confusion. The more noble and precisely-defined ex- pressions of system of the ivorld, the planetary ivorld, and creation and age of the ivorld, relate either to the totality of the substances by which space is filled, or to the origin of" the whole universe.

It was natural that, in the midst of the extreme variability of phenomena presented by the surface of our globe, and the aerial ocean by which it is surrounded, man should have been impressed by the aspect of the vault of heaven, and the uni- form and regular movements of the sun and planets. Thus the word Cosmos, which primitively, in the Homeric ages, in- dicated an idea of order and harmony, was subsequently adopt- ed in scientific language, where it was gradually applied to the order observed in the movements of the heavenly bodies, to the whole universe, and then finally to the world in which this harmony was reflected to us. According to the assertion of Philolaiis, whose fragmentary works have been so ably com- mented upon by Bockh, and conformably to the general testi-

INTRODUCTION. 69

mony of antiquity, Pythagoras was the first who used the word Cosmos to designate the order that reigns in the uni- verse, or entire world.*

* Koofioc, in the most ancient, and at the same time most precise, definition of the word, signified ornament (as an adornment for a man, a woman, or a horse) ; taken figuratively for evra^ia, it implied, the or- der or adornment of a discourse. According to the testimony of all the ancients, it was Pythagoras who first used the word to designate the order in the universe, and the universe itself. Pythagoras left no writ- ings ; but ancient attestation to the truth of this assertion is to be found in several passages of the fragmentary works of Philolatis (Stob., Eclog., p. 360 and 460, Heeren), p. 62, 90, in Bockh's German edition. I do not, according to the example of Niike, cite Tim.'eus of Locris, since hia authenticity is doubtful. Plutarch {De plac. Phil., ii., 1) says, in the most express manner, that Pythagoras gave the name of Cosmos to the universe on account of the order which reigned throughout it; so like- wise does Galen {Hist. Phil., p. 429). This word, together with its novel signification, passed from the schools of philosophy into the lan- guage ot poets and prose writers. Plato designates the heavenly bod- ies by the name of Uranos, but the order pervading the regions of space he too terms the Cosmos, and in his Timmus (p. 30, b.) he says that the world is an animal endowed tcith a soul {KOCfiov ^cjou kiiypv^ov). Com- pare Anaxag. Claz., ed. Schaubach, p. Ill, and Plut. {De plac. Phil., ii., 3), on spirit apart from matter, as the ordaining power of nature. In Aristotle {De Casio, 1, 9), Cosmos signifies " the universe and the order pervading it," but it is likewise considered as divided in space into two parts — the sublunary world, and the world above the moon. {Meteor., I., 2, 1, and I., 3, 13, p. 339, a, and 340, b, Bekk.) The def- inition of Cosmos, which I have already cited, is taken from Pseudo-Ar- istoteles de Mundo, cap. ii. (p. 391); tte passage referred to is as fol- lows: Koa^og earl nvoTijua kg ovpavov koL yfjg Kul tuv ev Tovrotg Trepte- XOfiivuif (pvaeov. AeyeTac de Kal eKepcog K6a2,og rj ribv bT^uv rd^ig re kuI 6iaK6(yfj,r]aig, vno t^euv re Kai did d^aijv (pv/iaTTOfiivri. Most of the pas- sages occurring in Greek writers on the word Cosmos may be found collected together in the controversy between Richard Bentley and Charles Boyle {Opuscula Philologica, 1781, p. 347, 445; Dissertation iipon the Epistles of Phalaris, 1817, p. 254) ; on the histoiical existence of Zaleucus, legislator of Leucris, in Nake's excellent work, Sched. Crit., 1812, p. 9, 15; and, finally, in Thcophilus Schmidt, ad Cleom. Cycl. Theor., met. I., 1, p. ix., 1, and 99. Taken in a more limited sense, the word Cosmos is also used in the plural (Plut., 1, 5), either to designate the stars (Stob., 1, p. 514; Plut., 11, 13), or the innumerable systems scattered like Islands through the immensity of space, and each composed of a sun and a moon. (Anax. Claz., Fragm., p. 89, 93, 120; Brandis, Gesck. der Griechisck-Romischen Philosophie, h. i., s. 252 (His- tory of the Greco-Roman Philosophy). Each of these groups forming thus a Cosmos, the universe, to ttuv, the word must be understood in a wider sense (Pint., ii., 1). It was not until long after the time of the Ptolemies that the word was applied to the earth. Bockh has made known inscnptions in praise of Trajan and Adrian ( Corpus Inscr. Grcec., 1, n. 334 and 1036), in which Koafiog occurs for oLKOVjiivrj, in the same manner as we still use the term world to signify the earth alone. We have already mentioned the singular division of the regions of space

70 COSMOS.

From the Italian school of philosophy, the expression pass- ed, in this signification, into the language of those early poets

into three parts, the Olympus, Cosmos, and Oui\tnos (Stob., i., p. 488; Philolatis, p. 94, 202) ; this division applies to the dilTerent regions sur i-Qunding that mysterious focus of the universe, the 'Earia rov iravTot, of the Pythagoreans. In the fragmentary passage in which this divi- sion is found, the term Ouranos designates the innermost region, situ- ated between the moon and earth ; this is the domain of changing things. The middle region, where the planets circulate in an invaria- ble and harmonious order, is, in accordance with the special coucep- tions entertained of tlie universe, exclusively termed Cosmos, while the word Olympus is used to express the exterior or igneous region. 13opp, the profound philologist, has remarked, that we may deduce, as Pott has done, Etymol. Forschungeii, th. i., s. 39 and 252 {Eiymol. Research- es), the word Koa^og from the Sanscrit root 'sud\ purificari, by assum- ing two conditions; first, that the Greek k in koo^oq comes from the palatial c, which Bopp represents by 's and Pott by c (in the same man- ner as diKa, decern, taih^m in Gothic, comes from the Indian word del- ean), and, next, that the Indian d' corresponds, as a general rule, with the Greek 6 ( Vergleichende Grammatik, $ 99 — Comparative Grammar), which shows the relation of Koa/xoc (for Kodfxog) with the Sanscrit root ^sud\ whence is also derived Kada^ibg. Another Indian term for the world is gagat (pronounced dschagat), which is, properly speaking, the present participle of the verb gagdmi (I go), the root of which is gd. In restricting ourselves to the circle of Hellenic etymologies, we find {Etymol. M., p. 532, 12) that Koojiog is intimately associated with wafw, or rather with Kacvvfiac, whence we have KeKaafievog or KCKac^fxEvog. Welcker (Eine Kretische Col. in Thebcn, s. 23 — A Cretan Colony in Thebes) combines with this the name Kadjiog, as in Hesychius Kud/nog signifies a Cretan suit of anus. When the scientific language of Greece w^as introduced among the Romans, the word mundus, which at first had only the primary meaning of /cda/^of (female ornament), was applied to designate the entire universe. Ennius seems to have been the first who ventui-ed upon this innovation. In one of the fragments of this poet, preserved by Macrobius, on the occasion of his quarrel with Vir- gil, we fiud the word used in its novel mode of acceptation : " Micitdus coeli vastus constitit silentio''^ (Sat., vi., 2). Cicero also says, ^'Qvem nos lucentem mundum vocamus^^ (Timajus, S. de Univer., cap. x.). The Sanscrit root mand, from which Pott derives the Latin mundus {Etym. Forsch., th. i.,s. 240), combines the double signification of shining and adorning. Loka designates in Sanscrit the world and people in general, in the same manner as the French word monde, and is derived, accord- ing to Bopp, from Idk (to see and shine); it is the same with the Scla- vonic root swjet, which means both light and icorld. (Grimm, Deutsche Gramm., b. iii., s. 394 — German Grammar.) The word icelt, which the Germans make use of at the present day, and which was weralt in old German, toorold in old Saxon, and veruld in Anglo-Saxon, was, ac- cording to .Tames Grimm's interpi-etation, a period ol time, an age (««- cnlum), rather than a term used for the world in space. The Etruscans figured to themselves mundus as an inverted dome, symmetrically op- posed to the celestial vault (Otfried MUller's Etrusken, th. ii., s. 96, &c.). Taken in a still more hmited sense, the word appears to have signified among the Goths the terrestrial surface girded by seas (marei, meri), the merigard, literally, garden of seas.

INTRODUCTION. 71

of nature, Parmenides and Empedocles. and from thence into the works of prose writers. We will not here enter into a discussion of the manner in which, according to the Pythago- rean views, Philolaiis distinguishes between Olympus, Uranus, or the heavens, and Cosmos, or how the same word, used in a plural sense, could be applied to certain heavenly bodies (the planets) revolving round one central focus of the world, or to groups of stars. In this work I use the word Cosmos in conformity with the Hellenic usage of the term subsequently to the time of Pythagoras, and in accordance with the precise definition given of it in the treatise entitled De Mmido, which was long erroneously attributed to Aristotle. It is the assem- blage of all things in heaven and earth, the universality of created things constituting the perceptible world. If scientific terms had not long been diverted from their true verbal sig- nification, the present work ought rather to have borne the title of Cosmography, divided into Uranography and Geog- raj)hy. The Romans, in their feeble essays on philosophy, ^ imitated the Greeks by applying to the universe the term inundus, which, in its primary meaning, indicated nothing more than ornament, and did not even imply order or regu- larity in the disposition of parts. It is probable that the in- troduction into the language of Latium of this technical term as an equivalent for Cosmos, in its double signification, is due to Ennius,* who was a follower of the Italian school, and the translator of the writings of Epicharmus and some of his pu pils on the Pythagorean philosophy.

We would first distinguish between the physical history and the physical description of the world. The former, conceived in the most general sense of the word, ought, if materials for writing it existed, to trace the variations experienced by the universe in the course of ages from the new stars which have suddenly appeared and disappeared in the vault of heaven, from nebula} dissolving or condensing — to the first stratum of cryptogamic vegetation on the still imperfectly cooled surface of the earth, or on a reef of coral uplifted from the depths of ocean. The physical description of the ivorld presents a pic- ture of all that exists in space — of the simultaneous action of

* See, on Ennius, the ingenious researches of Leopold Krahnev, in liis Grundlinien ziir GeschicJite des Verfalls der Romischen Staats-Rcii gion, 1837, s. 41-45 (Outlines of the History of the Decay of the EstaU lished Religion among the Romans). In all probability, Ennius did not quote from writings of Epicharmus himself, but from poems composed La the name of that philosopher, and in accordance wi'h his views

72 COSMOS.

natural forces, together with the phenomena which they pro- duce.

But if we would correctly comprehend nature, we must not entirely or absolutely separate the consideration of the present state of things from that of the successive phases through which they have passed. We can not form a just conception of their nature without looking back on the mode of their for- mation. It is not organic matter alone that is continually un- dergoing change, and being dissolved to form new combina- tions. The globe itself reveals at every phase of its existence the mystery of its former conditions.

We can not survey the crust of our planet without recog- nizing the traces of the prior existence and destruction of an organic world. The sedimentary rocks present a succession of organic forms, associated in groups, Avhich have successive- ly displaced and succeeded each other. The different super imposed strata thus display to us the faunas and floras of dif- ferent epochs. In this sense the description of nature is inti mately connected with its history ; and the geologist, who is guided by the connection existing among the facts observed, can not form a conception of the present without pursuing, through countless ages, the history of the past. In tracing the physical delineation of the globe, we behold the present and the past reciprocally incorporated, as it were, with one another ; for the domain of nature is like that of languages, in which etymological research reveals a successive development, by showing us the primary condition of an idiom reflected in the forms of speech in use at the present day. The study of the material world renders this reflection of the past peculiar- ly manifest, by displaying in the process of formation rocks of eruption and sedimentary strata similar to those of former ages. If I may be allowed to borrow a striking illustration from the geological relations by which the physiognomy of a country is determined, I would say that domes of trachyte, cones of basalt, lava streams {coulees) of amygdaloid with elongated and parallel pores, and white deposits of pumice, intermixed with black scoriae, animate the scenery by the as- sociations of the past which they awaken, actmg upon the imagination of the enlightened observer like traditional records of an earlier world. Their form is their history.

The sense in which the Greeks and Romans originally em- ployed the word history proves that they too were intimately convinced that, to form a complete idea of the present state of the universe, it was necessary to consider it in its successive

INTRODUCTION. 73^

phases. It is not, however, in the definition given by Vale- lius Flaccus,*' but in the zoological writings of Aristotle, that the word history presents itself as an exposition of the results of experience and observation. The physical description of the word by Pliny the elder bears the title of Natural His- tory, while in the letters of his nephew it is designated by the nobler terra of History of Nature. The earlier Greek his- torians did not separate the descriptions of countries from the narrative of events of which they had been the theater. With these writers, physical geography and history were long inti- mately associated, and remained simply but elegantly blended until the period of the development of political interests, when the agitation in which the lives of men were passed caused the geographical portion to be banished from the history of nations, and raised into an independent science.

It remains to be considered whether, by the operation of thought, we may hope to reduce the immense diversity of phenomena comprised by the Cosmos to the unity of a princi- ple, and the evidence ajSbrded by rational truths. In the present state of empirical knowledge, we can scarcely flatter ourselves Avith such a hope. Experimental sciences, based on the observation of the external world, can not aspire to completeness ; the nature of things, and the imperfection of our organs, are alike opposed to it. We shall never succeed in exhausting the immeasurable riches of nature ; and no gen- eration of men will ever have cause to boast of bavins: com- prehended the total aggregation of phenomena. It is only by distributing them into groups that we have been able, in the case of a few, to discover the empire of certain natural laws, grand and simple as nature itself. The extent of this empire will no doubt increase in proportion as physical sciences are more perfectly developed. Striking proofs of this advance- ment have been made manifest in our own day, in the phe- nomena of electro-magnetism, the propagation of luminous waves and radiating heat. In the same manner, the fruitful doctrine of evolution shows us how, in organic development, all that is formed is sketched out beforehand, and how the tissues of vegetable and animal matter uniformly arise from the multiplication and transformation of cells.

The generalization of laws, which, being at first bounded by narrow limits, had been applied solely to isolated groups of phenomena, acquires in time more marked gradations, and gains in extent and certainty as long as the process of reason*

* Aul. Gell.. Noct. Alt., v., 18.

Vol. I— D

74 COSMOS.

ing is applied strictly to analogous phenomena ; but as soon as dynamical views prove insufficient M'here the specific prop- erties and heterogeneous nature of matter come into play, it is to he feared that, by persisting in the pursuit of laws, we may find our course suddenly arrested by .an impassable chasm. The principle of unity is lost sight of, and the guiding clew is rent asunder whenever any specific and peculiar kind of action manifests itself amid the active forces of nature. The law of equivalents and the numerical proportions of composi- tion, so happily recognized by modern chemists, and proclaimed under the ancient form of atomic symbols, still remains isola- ted and independent of mathematical laws of motion and grav- itation.

Those productions of nature which are objects of direct ob- servation may be logically distributed in classes, orders, and families. This form of distribution undoubtedly sheds some light on descriptive natural history, but the study of organized bodies, considered in their linear connection, although it may impart a greater degree of unity and simplicity to the distri- bution of groups, can not rise to the height of a classification based on one sole principle of composition and internal organ- ization. As different gradations are presented by the laws of nature according to the extent of the horizon, or the limits of the phenomena to be considered, so there are likewise dif- ferently graduated phases in the investigation of the external world. Empiricism originates in isolated views, which are subsequently grouped according to their analogy or dissimilar- ity. To direct observation succeeds, although long afterward, the wish to prosecute experiments ; that is to say, to evoke phenomena under different determined conditions. The ra- tional experimentalist does not proceed at hazard, but acts under the guidance of hypotheses, founded on a half indistinct and more or less just intuition of the connection existing among natural objects or forces. That which has been conquered by observation or by means of experiments, leads, by analysis and induction, to the discovery of empirical laws. These are the phases in human intellect that have marked the different epochs in the life of nations, and by means of which that great mass of facts has been accumulated which constitutes at the present day the solid basis of the natural sciences.

Two forms of abstraction conjointly regulate our knowl- edge, namely, relations of quantity, comprising ideas of num- ber and size, and relations of quality, embracing the consider- ation of the specific properties and the heterogeneous nature

INTRODUCTION. 76

of matter. The former, as being more accessible to the exer cise of thought, appertains to mathematics ; the latter, from its apparent mysteries and greater difficulties, falls under the domain of the chemical sciences. In order to submit phe- nomena to calculation, recourse is had to a hypothetical con- struction of matter by a combination of molecules and atoms, whose number, form, position, and polarity determine, modify, or vary phenomena.

The mythical ideas long entertained of the imponderable substances and vital forces peculiar to each mode of organiza- tion, have complicated our views generally, and shed an un- certain light on the path we ought to pursue.

The most various forms of intuition have thus, age aftei age, aided in augmenting the prodigious mass of empirical knowledge, which in our own day has been enlarged with ever-increasing rapidity. The investigating spirit of man strives from time to time, with varying success, to break through those ancient forms and symbols invented, to subject rebellious matter to rules of mechanical construction.

We are still very far from the time when it will be possi- ble for us to reduce, by the operation of thought, all that we perceive by the senses, to the unity of a rational principle. It may even be doubted if such a victory could ever be achieved in the field of natural philosophy. The complica- tion of phenomena, and the vast extent of the Cosmos, would seem to oppose such a result ; but even a partial solution of the problem — the tendency toward a comprehension of the phenomena of the universe — will not the less remain the eter- nal and sublime aim of every investigation of nature.

In conformity with the character of my former writings, as well as with the labors in which I have been engaged during my scientific career, in measurements, experiments, and the investigation of facts, I limit myself to the domain of empirical ideas.

The exposition of mutually connected facts does not exclude the classification of phenomena according to their rational con- nection, the generalization of many specialities in the great mass of observations, or the attempt to discover laws. Con- ceptions of the universe solely based upon reason, and the principles of speculative philosophy, would no doubt assign a still more exalted aim to the science of the Cosmos. I am far from blaming the efforts of others solely because their success has hitherto remained very doubtful. Contrary to the wishes and counsels of those profound and powerful thinkers who

76 COSMOS.

have given new life to speculations which were already fa- miliar to the ancients, systems of natural philosophy have in our own country for some time past turned aside the minds of men from the graver study of mathematical and physical sciences. The abuse of better powers, which has led many of our noble but ill-judging youth into the saturnalia of a pure- ly ideal science of nature, has been signalized by the intoxica- tion of pretended conquests, by a novel and fantastically sym- bolical phraseology, and by a predilection for the formulae of a scholastic rationalism, more contracted in its views than any known to the Middle Ages. I use the expression " abuse of better powers," because superior intellects devoted to phil- osophical pursuits and experimental sciences have remained strangers to these saturnalia. The results yielded by an earn- est investigation in the path of experinient can not be at va- riance with a true philosophy of nature. If there be any contradiction, the fault must lie either in the unsoundness of speculation, or in the exaggerated pretensions of empiricism, which thinks that more is proved by experiment than is act- ually derivable from it.

External nature may be opposed to the intellectual world, as if the latter were not comprised within the limits of the former, or nature may be opposed to art when the latter is defined as a manifestation of the intellectual power of man ; but these contrasts, which we find reflected in the most cul- tivated languages, must not lead us to separate the sphere of nature from that of mind, since such a separation would re- duce the physical science of the world to a mere aggregation of empirical specialities. Science does not present its.elf to man until mind conquers matter in striving to subject the result of experimental investigation to rational combinations. Science is the labor of mind applied to nature, but the ex- ternal world has no real existence for us beyond the image reflected within ourselves through the medium of the senses. As intelligence and forms of speech, thought and its verbal symbols, are united by secret and indissoluble links, so does the external world blend almost unconsciously to ourselves with our ideas and feelings. " External phenomena," says Hegel, in his Philosophy of History, " are in some degree translated in our inner representations. ' ' The objective world, conceived and reflected, within us by thought, is subjected to the eternal and necessary conditions of our intellectual being. The activity of the mind exercises itself on the elements fur- nished to it by the perceptions of the senses. Thus, in the

INTRODUCTION. 77

early ages of mankind, there manifests itself in the simple in- tuition of natm*al facts, and in the efforts made to compre- hend them, the germ of the philosophy of nature. These ideal tendencies vary, and are more or less powerful, accord- ing to the individual characteristics and moral dispositions of nations, and to the degrees of their mental culture, whether attained amid scenes of nature that excite or chill the imag- ination.

History has preserved the record of the numerous attempts that have been made to form a rational conception of the whole world of phenomena, and to recognize in the universe the action of one sole active force by which matter is pene- trated, transformed, and animated. These attempts are traced in classical antiquity in those treatises on the principles of things which emanated from the Ionian school, and in which all the phenomena of nature were subjected to hazardous speculations, based upon a small number of observations. By degrees, as the influence of great historical events has favored the development of every branch of science supported by ob- servation, that ardor has cooled which formerly led men to seek the essential nature and connection of things by ideal construction and in purely rational principles. In recent times, the mathematical portion of natural philosophy has been most remarkably and admirably enlarged. The method and the instrument (analysis) have been simultaneously per- fected. That which has been acquired by means so different — by the ingenious application of atomic suppositions, by the more general and intimate study of phenomena, and by the improved construction of new apparatus — is the common prop- erty of mankind, and should not, in our opinion, now, more than in ancient times, be withdrawn from the free exercise of speculative thought.

It can not be denied that in this process of thought the results of experience have had to contend with many disad- vantages ; we must not, therefore, be surprised if, in the per- petual vicissitude of theoretical views, as is ingeniously ex- pressed by the author of Giordano Bi'uno,^ " most men see nothing in philosophy but a succession of passing meteors, while even the grander forms in which she has revealed her- self share the fate of comets, bodies that do not rank in pop- ular opinion among the eternal and permanent works of na-

* SchelUug's Bruno, TJeher das Goitliche und Naturaliche Princip der Dingc, $ 181 (Bruno, on the Divine and Natural Principle of Things)

78 coSxMos.

ture, but are regarded as mere fugitive apparitions of igiioo«/s vapor." We would here remark that the abuse of thought, and the false track it too often pursues, ought not to sanctian an opinion derogatory to intellect, vi^hich would imply that the domain of mind is essentially a world of vague fantastic illusions, and that the treasures accumulated by laborious ob- servations in philosophy are powers hostile to its own empire. It does not become the spirit which characterizes the present age distrustfully to reject every generalization of views and every attempt to examine into the nature of things by the process of reason and induction. It would be a denial of the dignity of human nature and the relative importance of the faculties with which we are endowed, were we to condemn at one time austere reason engaged in investigating causes and their mutual connections, and at another that exercise of the imagination which prompts and excites discoveries by its creative powers.

COSMOS.

DELINEATION OF NATURE. GENERAL REVIEW OF NATURAL PHENOMENA.

When the human mind first attempts to subject to its con- trol the world of physical phenomena, and strives by medita- tive contemplation to penetrate the rich luxuriance of living nature, and the mingled web of free and restricted natural forces, man feels himself raised to a height from whence, as he embraces the vast horizon, individual things blend together in varied groups, and appear as if shrouded in a vapory vail. These figurative expressions are used in order to illustrate the point of view from whence we would consider the universe both in its celestial and terrestrial sphere. I am not insen- sible of the boldness of such an undertaking. Among all the forms of exposition to which these pages are devoted, there is none more difficult than the general delineation of nature, which we purpose sketching, since we must not allow our- selves to be overpowered by a sense of the stupendous rich- ness and variety of the forms presented to us, but must dwell only on the consideration of masses either possessing actual magnitude, or borrowing its semblance from the associations aAvakened within the subjective sphere of ideas. It is by a separation and classification of phenomena, by an intuitive in- sight into the play of obscure forces, and b/ animated expres- sions, in which the perceptible spectacle is i\ fleeted with vivid truthfulness, that we may hope to compreh^^nd and describe the universal all (to Tray) in a manner worthy of the dignity of the word Cosmos m its signification of tiniverse, order of the U'orld, and adornment of this universal order. May the ijumeasurable diversity of phenomena which crowd into the picture of nature in no way detract from that harmonious im- pression of rest and unity v/hich is the ultimate object of every literary or purely artistical composition.

Beginning with the depths of space and the regions of re- motest nebulse, Vv-e will gradually descend through the starry zone to which our solar system belongs, to our own terrestrial spheroid, circled by air and ocean, there to direct our atten-

80 COSMOS

tion to its form, temperature, and magnetic tension, and to consi'ler the fullness of organic life unfolding itself upon its surface beneath the vivifying influence of light. In this man- ner a picture of the world may, with a few strokes, be made to include the realms of infinity no less than the minute mi- croscopic animal and vegetable organisms which exist in stand- ing waters and on the weather-beaten surface of our rocks. All that can be perceived by the senses, and all that has been accumulated up to the present day by an attentive and vari- ously directed study of nature, constitute the materials from which this representation is to be drawn, whose character is an evidence of its fidelity and truth. But the descriptive pic- ture of nature which we purpose drawing must not enter too fully into detail, since a minute enumeration of all vital forms, natural objects, and processes is not requisite to the complete- ness of the undertaking. The delineator of nature must re- sist the tendency toward endless division, in order to avoid the dangers presented by the very abundance of our empirical knowledge. A considerable portion of the qualitative proper^, ties of matter — -or, to speak more in accordance with the lan- guage of natural philosophy, of the qualitative expression of forces — is doubtlessly still unknown to us, and the attempt perfectly to represent unity in diversity must therefore neces- sarily prove unsuccessful. Thus, besides the pleasure derived from acquired knowledge, there lurks in the mind of man, and tinged with a shade of sadness, an unsatisfied longing for something beyond the present — a striving towaixl regions yet unknown and unopened. Such a sense of longing binds still ■aster the links which, in accordance with the supreme laws of our being, connect the material with the ideal world, and animates the mysterious relation existing between that which the mind receive^ from without, and that which it reflects from its own dej ths to the external world. If, then, nature (understanding by the term all natural objects and phenomena) be illimitable in extent and contents, it likewise presents it- self to the haman intellect as a problem which can not be grasped, a.nd whose solution is impossible, since it requires a knowledge of che combined action of all natural forces. Such an acknowledgment is due where the actual state and pro- spective development of phenomena constitute the sole objects of direct investigation, which does not venture to depart from the strict rules of induction. But, although the incessant ef- fort to embrace nature in its universality may remain unsatis- fied, the history of the contemplation of the universe (which

DELINEATION OF NATURE. 81

Will be considered in another part of this work) will teach us how, in the course of ages, mankind has gradually attained to a partial insight into the relative dependence of phenomena. My duty is to depict the results of our knowledge in all their bearings with reference to the present. In all that is subject to motion and change in space, the ultimate aim, the very ex- pression of physical laws, depend upon inean mimerical value?,. which show us the constant amid change, and the stable amid apparent fluctuations of phenomena. Thus the progress of modern physical science is especially characterized by the at- tainment and the rectification of the mean values of certain quantities by means of the processes of weighing and meas- uring ; and it may be said, that the only remaining and wide- ly-difiused hieroglyphic characters still in our writing — nimi- bers — appear to us again, as powers of the Cosmos, although in a wider sense than that applied to them by the Italian School.

The earnest investigator delights in the simplicity of nu- merical relations, indicating the dimensions of the celestial regions, the magnitudes and periodical disturbances of the heavenly bodies, the triple elements of terrestrial magnetism, the mean pressure of the atmosphere, and the quantity of heat which the sun imparts in each year, and in every season of the year, to all points of the solid and liquid surface of our planet. These sources of enjoyment do not, however, satisfy the poet of Nature, or the mind of the inquiring many. To both of these the present state of science appears as a blank, now that she answers doubtingly, or wholly rejects as unanswerable, questions to which former ages deemed they could furnish satisfactory rephes. In her severer aspect, and clothed with less luxuriance, she shows herself deprived of that seductive charm with which a dogmatizing and symbolizing physical philosophy knew how to deceive the understanding and give the rein to imagination. Long before the discovery of the New World, it was believed that new lands in the Far West might be seen from the shores of the Canaries and the Azores. These illusive images were owing, not to any extraordinary refraction of the rays of light, but produced by an eager long- ing for the distant and the unattained. The philosophy of the Greeks, the physical views of the Middle Ages, and even those of a more recent period, have been eminently imbued with the charm springing from similar illusive phantoms of the imagination. At the limits of circumscribed knowledge, as from some lofty island shore, the eye delights to penetrate

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82 COSMOS.

to distant regions. The belief in the uncommon and the won- derful lends a definite outline to every manifestation of ideal creation ; and the realm of fancy — a fairy-land of cosmolog- ical, geognostical, and magnetic visions — becomes thus invol- untarily blended vv^ith the domain of reaUty.

Nature, in the manifold signification of the word — whether considered as the universality of all that is and ever will be — as the inner moving force of all phenomena, or as their mys- terious prototype — reveals itself to the simple mind and feel- ings of man as something earthly, and closely allied to him- self It is only within the animated circles of organic struc- ture that we feel ourselves peculiarly at home. Thus, wherever the earth unfolds her fruits and flowers, and gives food to countless tribes of animals, there the image of nature impresses itself most vividly upon our senses. The impression thus produced upon our minds limits itself almost exclusively to the reflection of the earthly. The starry vault and the wide expanse of the heavens belong to a picture of the uni- verse, in which the magnitude of masses, the number of con- gregated suns and faintly glimmering nebulae, although they excite our wonder and astonishment, manifest themselves to us in apparent isolation, and as utterly devoid of all evidence of their being the scenes of organic life. Thus, even in the earliest physical views of mankind, heaven and earth have been separated and opposed to one another as an upper and lower portion of space. If, then, a picture of nature were to correspond to the requirements of contemplation by the senses, it ought to begin with a delineation of our native earth. It should depict, first, the terrestrial planet as to its size and form ; its increasing density and heat at increasing depths in its superimposed solid and liquid strata ; the separation of sea and land, and the vital forms animating both, developed in the cellular tissues of plants and animals ; the atmospheric ocean, with its waves and currents, through which pierce the forest-crowned summits of our mountain chains. After this delineation of purely telluric relations, the eye would rise to the celestial regions, and the Earth would then, as the well- known seat of organic development, be considered as a planet, occupying a place in the series of those heavenly bodies which circle round one of the innumerable host of self-luminous stars. This succession of ideas indicates the course pursued in the earliest stages of perceptive contemplation, and reminds us of the ancient conception of the " sea-girt disk of earth," sup- porting the vault of heaven. It begins to exercise its action

at the spot where it originated, and passes from the consider- ation of the known to the unknown, of the near to the distant It corresponds with the method pursued in our elementary works on astronomy (and which is so admirable in a mathe- matical point of view), of proceeding from the apparent to the real movements of the heavenly bodies.

Another course of ideas must, however, be pursued in a work which proposes merely to give an exposition of what is known — of what may in the present state of our knowledge be regarded as certain, or as merely probable in a greater or lesser deofree — and does not enter into a consideration of the proofs on which such results have been based. Here, there- fore, we do not proceed from the subjective point of view of human interests. The terrestrial must be treated only as a part, subject to the whole. The view of nature ought to be grand and free, uninfluenced by motives of proximity, social sympathy, or relative utility. A physical cosmography — a picture of the universe — does not begin, therefore, with the terrestrial, but with that which fills the regions of space. But as the sphere of contemplation contracts in dimension our per- ception of the richness of individual parts, the fullness of phys- ical phenomena, and of the heterogeneous properties of mat- ter becomes enlarged. From the regions in which we rec- ognize only the dominion of the laws of attraction, Ave de- scend to our own planet, and to the intricate play of terrestrial forces. The method here described for the delineation of na- ture is opposed to that which must be pursued in establish- ino- conclusive results. The one enumerates what the other demonstrates.

Man learns to know the external world through the organs of the senses. Phenomena of light proclaim the existence of matter in remotest space, and the eye is thus made the me- dium through which we may contemplate the universe. The discovery of telescopic vision more than two centuries ago, has transmitted to latest generations a power whose limits are as yet unattained.

The first and most general consideration in the Cosmos is that of the contents of space — the distribution of matter, or of creation, as we are wont to designate the assemblage of all that is and ever will be developed. We see matter either agglomerated into rotating, revolving spheres of different dens- ity and size, or scattered through space in the form of self- luminous vapor. If we consider first the cosmical vapor dis persed in definite nebulous spots, its state of aggregation will

84 COSMOS.

appear constantly to vary, sometimes appearing separated into round or elliptical disks, single or in pairs, occasionally con- nected by a thread of light ; while, at another time, these* nebulae occur in forms of larger dimensions, and are either elongated, or variously branched, or fan-shaped, or appear like well-defined rings, inclosing a dark interior. It is conjectured that these bodies are undergoing variously developed formative processes, as the cosmical vapor becomes condensed in con- formity with the laws of attraction, either round one or more of the nuclei. Between two and three thousand of such un- resolvabie nebulae, in which the most powerful telescopes have