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UNIVERSITY OF CALIFORNIA.

FROM THE LIBRARY OF

DR. JOSEPH LECONTE.

GIFT OF MRS. LECONTE.

No.

COSMOS:

SKETCH

OF A

PHYSICAL DESCRIPTION OP THE UNIVERSE.

BY

ALEXANDER VON HUMBOLDT.

VOL. I.

Katora vero rerwm vis atque majestas in omnibus momentisfide caret, si quis modoparta gut ac non totam complectatur animo. PLIN. H. N. lib. vii. c. 1.

TRANSLATED UNDER THE SUPERINTENDENCE OF

LIEUT.-COL. EDWARD SABINE, R.A., FOR. SEC. R.S.

IStrttion.

LONDON:

PRINTED FOB

LONGMAN, BROWN, GREEN, AND LONGMANS,

PATERNOSTEE ROW : AND

JOHN MURRAY, ALBEMARLE STREET. 1849.

PREFACE

TO THE SIXTH EDITION.

THE Editor's attention has been called to a passage in the Preface of another translation of " Cosmos," published by Mr. Bohn, wherein it is stated, that, in Mrs. SABINE'S translation, passages are omitted, "sometimes amounting to pages, simply because they might be deemed slightly obnoxious to our national prejudices." In justice to the respected Author of "Cosmos," the Editor is induced to state, that no passage whatever of M. DE HUHBOLDT'S writing has been omitted for the reason assigned. The only intentional omission of even a single sentence of M. DE HUMBOLDT'S writing is of a remark in Note 143 of Yolume I. (English translation), on the intermission of observations of extraordinary magnetic disturbance at the British Colonial Observatories, when such phsenomena occur on a Sunday. Shortly after the publication of the original

•829

EDITOR'S PREFACE.

The two introductory discourses, which occupy 48 pages in the German edition, have been rewritten by M. de Humboldt himself in the French language, for the French edition, in which they fill 78 pages. These were commu- nicated to the Editor in their passage through the press, and by the Author's desire have been followed in preference to the corresponding portion of the German text, where modifications or additions had been introduced.

Short as the interval has been, since Cosmos was written, it has not been unmarked by the progress which has been made in several branches of scientific knowledge. In astronomy it has been distinguished by the discovery of a new planet, Astrea, making the number of those bodies belonging to our solar system twelve instead of eleven: also of the two heads of Biela's comet, a phenomenon pre- viously unknown. These discoveries, however, in no respect affect the reasonings in Cosmos. The optical means at the command of astronomers have also been improved, by the construction of a telescope of unparalleled dimensions by the Earl of Rosse : and the few trials which have yet been made of its powers, lead to the belief, that the greater part, if not the whole, of the nebulse will be resolved by it into stars : happily the Author of Cosmos will himself have an opportunity, in the succeeding volumes, of stating the influence which a discovery of this nature may exercise

EDITOB'S PBEFACE*

upon the view which has been taken of the Celestial Phe- nomena in the volume now published.

It has been M. de Humboldt' s wish, and kindly pressed by him, that the Editor should add such notes as he might think desirable, particularly in the branches of science in which he has himself engaged : he has felt the propriety of exercising this privilege very sparingly, and has only availed himself of it in additions to Notes 132, 136, 139, 143, 158, 179, 373, and 382*.

Measures of itinerary distance are expressed in the origi- nal work in geographical miles of 15 to the degree; these have been converted in the translation into geographical miles of 60 to the degree, as more consonant to English usage. Measures of length are expressed by M. de Hum- boldt usually in French feet and toises, v hic'i have been retained in the translation; but the equivalent values in English feet have been added whenever it has appeared de- sirable to do so. In like manner the measures of tempera- ture in Fahrenheit's scale have been given MI addition to those in the Centesimal scale

"WOOLWICH, AUG. 22, 1846.

* A short addition has also heen made to Note 381 in the second edition} and an index of names and subjects has been appended. May 7, 1547.

CONTENTS.

P«ge

THE AUTHOR'S PREFACE . x?ii

INTRODUCTION.

On the different degrees of enjoyment offered by the aspect of Nature and the study of her laws 3

Limits and method of exposition of the Physical description of the universe . * . 42

GENERAL VIEW OF NATURE.

Introduction . . .67

CELESTIAL PHENOMENA.

Nebulae . 73

Sidereal systems 77

Our sidereal system 79

The solar system 81

Planets 82

Satellites 86

Comets 91

Aerolites 105

Zodiacal light .... 127

CONTENTS.

Page

The sun 134

Proper motions of stars 135

Double and multiple stars 136

Distances, masses, and apparent diameters of stars . . .137

Variable aspect of the heavens 138

Nebulous milky-way ^ ' -f* r't f\i ?f 4\'^\ * * -^

Successive propagation of light /•'»*• . . 143

TERRESTRIAL PHENOMENA.

General view 4 . . 145

Figure of the earth 154

Density of the earth . . j i<J'-'Vr '. .159

Internal heat of the earth 161

Mean temperature of the earth . ... .164

Terrestrial magnetism /'•• Vx '-•/>! , . . . 167 Polar light, or aurora . . . . , . . ] 79

Reaction of the interior of the earth on its exterior . . .189 Earthquakes . . > ,;fj ;,, r,;«; .,,,,., -;j *<,,.', . . 191 Eruptions of gas . ...'., + I..A 205

Hot and cold springs 207

Mud volcanoes . , . . . , . . 211 Volcanoes . < » 213

Geological description of the earth's crust .. . . . .235

Fundamental classification of rocks ..... 236

Endogenous or erupted rocks .'• . .. . 238

Exogenous or sedimentary rocks 241

Metamorphic rocks .- .' . . . , 244

Artificial production of simple minerals . . . .256 Conglomerates ..•.*.•.. . . 257 General chemical constituents of rocks . . . .258

Palaeontology Fossil organic remains 260

Palseozoology Fossil animals 261

Palseophytology Fossil plants * 268

Palseogeography— State of the surface of the globe at different geological epochs 274

CONTENTS.

Page

Physical Geography General view ...... 278

The land ........ . 280

The ocean ......... 294

The atmosphere Meteorology ...... 304

Atmospheric pressure ....... 308

Climatology ......... 312

Limit of perpetual snow ....... 327

Hygrometry ......... 330

Atmospherical electricity ....... 333

Mutual dependence of meteorological phenomena . , 326

ORGANIC LIFE.

General view ....... . . 338

Geography of plants and animals ...... 345

Man ........ ... 350

NOTES ...... . \

cxv

AUTHOR'S PREFACE.

IN the late evening of a varied and active life, I offer to tho German public a work of which the undefined type has been present to my mind for almost half a century. Often the scheme has been relinquished as one which I could not hope to realise, but ever after being thus abandoned, it has been again, perhaps imprudently, resumed. In now presenting its fulfilment to my contemporaries, with that hesitation which a just diffidence of my own powers could not fail to inspire, I would willingly forget that writings long expected are usually least favourably received.

While the outward circumstances of my life, and an irre- sistible impulse to the acquisition of different kinds of know- ledge, led me to occupy myself for many years, apparently exclusively, with sep arate branches of science, descriptive botany, geology, chemistry, geographical determinations, and terrestrial ma gnetism, tending to render useful the ex-

AUTHOR'S PREFACE.

tensive journeys in which I engaged,-r-I had still throughout a higher aim in view; I ever desired to discern physical phsenomena in their widest mutual connection, and to com- prehend Nature as a whole, animated and moved by inward forces. Intercourse with highly-gifted men had early led me to the- conviction, that without earnest devotion to particular studies such attempts could be but vain and illusory. The separate branches of natural knowledge have a real and intimate connection, which renders these special studies capable of mutual assistance and fructification : descriptive botany, no longer restricted to the narrow circle of the de- termination of genera and of species, leads the observer, who traverses distant countries and lofty mountains, to the study of the geographical distribution of plants according to dis- tance from the equator and elevation above the level of the sea. Again, in order to elucidate the complicated causes which determine this distribution, we must investigate the laws which regulate the diversities of climate and the meteo- rological processes of the atmosphere ; and thus the observer, earnest in the pursuit of knowledge, is led onwards from one class of phenomena to another, by their mutual connection. I have enjoyed one advantage which few scientific tra- vellers have shared to an equal degree, in having seen not merely coasts, and districts little removed from the margin of the ocean, as in voyages of circumnavigation, but in having,

moreover, traversed,, both in the new and the old world, extensive continental districts presenting the most striking contrasts ; on the one hand the tropical and alpine landscapes of Mexico and South America, and on the other the dreary uniformity of the steppes of Northern Asia. Such oppor- tunities could not fail to encourage the tendencies of a mind predisposed to generalisation, and were well fitted to animate me to the attempt of treating in a special work our present knowledge of the sidereal and terrestrial phenomena of the universe in their empirical connection. " Physical Geogra- phy/' the limits of which have been hitherto somewhat vaguely defined, has been thus expanded, by perhaps too bold a plan, into a scheme comprehending the whole material creation, or into that of a " Physical Cosmography."

Such a work, if it would aspire to combine with scientific accuracy any measure of success as a literary composition, has to surmount great difficulties, arising from the very abun- dance of the materials which the presiding mind must reduce to order and clearness, while yet the descriptions of the varied forms and phenomena of nature must not be deprived of the characteristic traits which give them life and animation. A series of general results would be no less wearisome than a mere accumulation of detached facts. I cannot venture to natter myself that I have adequately satisfied these various conditions, or avoided the dangers which I have not failed

to perceive ; the faint hope which I cherish of success rests on the particular favour which my countrymen have long bestowed on a small work which I published, soon after my return from Mexico, under the title of Ansichten der Natur, and which treated some portions of physical geography, such as the physiognomy of plants, savannahs, deserts, and cata- racts, under general points of view. Doubtless the effect which this small volume produced was far more attributable to its indirect action, in awakening the faculties of young and susceptible minds endowed with imaginative power, than to any thing which it could itself impart. In my present work, as in the one to which I have just alluded, I have endeavoured to shew practically, that a certain degree of scientific accuracy in the treatment of natural facts is not incompatible with animated and picturesque representation. Public discourses or lectures have always appeared to me well adapted to test the success or failure of an endeavour to unite detached branches of a general subject in a sys- tematic whole ; with this view a series of lectures on the Physical Description of the Universe, as I had conceived it, was delivered both in Berlin and in Paris, in German and in French. These discourses were not committed to writ- ing ; and even the notes preserved by the diligence of some attentive auditors have remained unknown to me ; nor have I chosen to have recourse to them in the execution of the

AUTHOll S PREFACE.

present work, the whole of which, with the exception of a portion of the Introduction, was written for the first time in the years ]843 and 1844; the discourses in Berlin having been delivered from November 1827 to April 1828, previous to my departure for Northern Asia. A represen- tation of the actual state of our knowledge, in which year by year the acquisitions of new observations imperatively demands the modification of previous opinions, must, as it appears to me, gain in unity, freshness, and spirit, by being definitely connected with some one determinate epoch.

The first volume contains a general view of nature, from the remotest nebulae and revolving double stars to the terrestrial phenomena of the geographical distribution of plants, of animals, and of races of men ; preceded by some preliminary considerations on i^ie different degrees of enjoy- ment offered by the study of nature and the knowledge of her laws ; and on the limits and method of a scientific ex- position of the physical description of the Universe. I regard this as the most important and essential portion of my undertaking, as manifesting the intimate connection of the general with the special, and as exemplifying in form and style of composition, and in the selection of the results taken from the mass of our experimental knowledge, the spirit of the method in which 1 have proposed to myself to

conduct the whole work. In the two succeeding VOL. i. c

I design to consider some of the particular incitements to the study of Nature, to treat of the history of the contem- plation of the physical universe, or the gradual development of the idea of the concurrent action of natural forces co-operating in all that presents itself to our observation,-— and lastly, to notice the specialities of the several branches of science, of which the mutual connection is indicated in the general view of nature in the present volume. References to authorities, together with details of observation, have been placed at the close of each volume, in the form of Notes. In the few instances in which I have introduced extracts from the works of my friends, they are indicated by marks of quotation ; and I have preferred the practice of giving the identical words, to any paraphrase or abridgment. The deli- cate and often contested questions of discovery and priority, so dangerous to introduce in an uncontroversial work, are rarely touched upon : the occasional references to classical antiquity, and to that liighly favoured transition period marked by the great geographical discoveries of the fifteenth and sixteenth centuries, have had for their principal motive, the wish, which is occasionally felt when dwelling on general

views of nature, to escape from the more severe and dogma-

.

tical restraint of modern opinions, into the free and imagi- native domain of earlier presentiments.

It has sometimes been regarded as a discouraging consi-

AUTHOR'S PREFACE.

deration, that whilst works of literature, being fast rooted fa the depths of human feeling, imagination, and reason, suffer little from the lapse of time, it is otherwise with works which treat of subjects dependent on the progress of experimental knowledge. The improvement of instruments, and the continued enlargement of the field of observation, render investigations into natural phenomena and physical laws liable to become antiquated, to lose their interest, and to cease to be read. Such reflections are not entirely desti- tute of foundation; yet none who are deeply penetrated with a true and genuine love of nature, and with a lively appreciation of the true charm and dignity of the study of her laws, can ever view with discouragement or regret that which is connected with the enlargement of the boundaries of our knowledge. Many and important portions of this knowledge, both as regards the phenomena of the celestial spaces and those belonging to our own planet, are already based on foundations too firm to be lightly shaken ; although in other portions, general laws will doubtless take the place of those which are more limited in their application, new forces will be discovered, and substances considered as simple will be decomposed, whilst others will become known. I venture, then, to indulge the hope, that the present attempt to trace in animated characters such a general view of the grandeur of nature, and of the perma-

nent relations and laws discernible through apparent fluc- tuation, as the knowledge of our own age permits us to form, will not be wholly disregarded ev*a at a future period.

POTSDAM, Nov. 1844.

A PHYSICAL DESCRIPTION OF THE UNIVERSE.

ON THE DIFFERENT DEGREES OF ENJOYMENT OFFERED BY

THE ASPECT OF NATURE AND THE STUDY

OF HER LA.WS.

IN attempting, after a long absence from my country, to unfold a general view of the physical phsenomena of the globe which we inhabit, and of the combined action of the forces which pervade the regions of space, I feel a double anxiety. The matter of which I would treat is so vast, and so varied, that I fear, on the one hand, to approach it in an encyclopaedic and superficial manner, and on the other, to weary the mind by aphorisms presenting only dry and dog« matic generalities. Conciseness may produce aridity, whilst too great a multiplicity of objects kept in view at the same time leads to a want of clearness and precision in the sequence of ideas. But nature is the domain of liberty; and to give a lively

4 ASPECT OF NATURE. AND

picture of those ideas and those delights which a true and profound feeling in her contemplation inspires, it is needful that thought should clothe itself freely and without con- straint in such forms and with such elevation of language, as may be least unworthy of the grandeur and majesty of creation.

If the study of physical phenomena be regarded in its bearings, not on the material wants of man, but on his general intellectual progress, its highest result is found in the knowledge of those mutual relations which link together the various powers of nature. It is the intuitive and intimate persuasion of the existence of these relations which at once enlarges and elevates our views, and enhances our enjoyment. Such extended views are the growth of observation, of medi- tation, and of the spirit of the age, which is ever reflected in the operations of the human mind whatever may be their direction. Those who by the light of history should trace back through past ages the progress of physical knowledge to its early and remote sources, would learn how for thousands of years the human mind has laboured to lay hold of the sure thread of the invariability of natural laws, amid the per- plexities of ceaseless change ; and in so doing has gradually conquered, so to speak, great part of the physical universe* In following back this mysterious track, still the same image of the Cosmos reappears, which, in its earlier revelation, shewed itself as a presentiment of the true harmony and order of the universe, and which, in our days, presents itself as the fruit of long-continued and laborious observation. Each of these two epochs of the contemplation of the ex- ternal world has its own proper enjoyment : that belonging to the first awakening of such reflections is well suited to

STUDY OP HER LAWS, 5

the simplicity of the earlier ages of the world ; to them the undisturbed succession of the planetary movements, and the progressive development of animal and vegetable life, were pledges of an order yet undiscovered in other relations, but of which they instinctively divined the existence. To us in an advanced civilisation belongs the enjoyment of the precise knowledge of phsenomena. From the time when man in interrogating nature began to experiment, or to produce phsenomena under definite conditions, and to collect and record the fruits of experience, so that investigation might no longer be restricted by the short limits of a single life, the philosophy of nature laid aside the vague and poetic forms with which she had at first been clothed, and has adopted a more severe cliaracter : she now weighs the value of observations, and no longer divines, but combines and reasons. Exploded errors may survive partially among the uneducated, aided in some instances by an obscure and mystic phraseology : they have also left behind them many expressions by which our nomenclature is more or less dis- figured ; while a few of happier, though figurative origin, have gradually received more accurate definition, and have been found worthy of preservation in our scientific language.

The aspect of external nature, as it presents itself in its generality to thoughtful contemplation, is that of unity in diversity, and of connection, resemblance and order, among created things most dissimilar in their form; one fair harmonious whole. To seize this unity and this harmony, amid such an immense assemblage of objects and forces,— to embrace alike the discoveries of the earliest ages and those of our own time, and to analyse the details of phsenomena without sinking under their mass, are efforts of human

6 DIFFERENT GRADATIONS OP

reason in the path wherein it is given to man to press towards the full comprehension of nature, to unveil a portion of her secrets, and, by the force of thought, to subject, so to speak, to his intellectual dominion, the rough materials which he collects by observation.

If we attempt to analyse the different gradations of enjoy- ment derived from the contemplation of nature, we find, first, an impression which is altogether independent of any know- ledge of the mode of action of physical powers, and which does not even depend on the particular character of the objects contemplated. When we behold a plain bounded by the horizon, and clothed by a uniform covering of any of the social plants (heaths, grasses, or cistusses), when we gaze on the sea, where its waves, gently washing the shore, leave behind them long undulating lines of weeds, then, while the heart expands at the free aspect of nature, there is at the same time revealed to the mind an impression of the y existence of comprehensive and permanent laws governing the phenomena of the universe. The mere contact with nature, the issuing forth into the open air, that which by an expression of deep meaning my native language terms in das Freie, exercises a soothing and a calming influence on the sorrows and on the passions of men, whatever may be the region they inhabit, or the degree of intellectual culture which they enjoy. That which is grave and solemn in these impressions is derived from the presentiment of order and of law/ unconsciously awakened by the simple contact with external nature ; it is derived from the contrast of the narrow limits of our being with that image of infinity, which every where reveals itself in the starry heavens, in the boundless plain, or in the indistinct horizon of the ocean.

THE ENJOYMENT OF NATUEE. 7

Other impressions, better defined, affording more vivid enjoyment and more congenial to some states of the mind, depend more on the peculiar character and physiognomy of the scene contemplated, and of the particular region of the earth to which it belongs. They may be excited by views the most varied ; either by the strife of nature, or by the barren monotony of the steppes of Northern Asia, or by the happier aspect of the wild fertility of nature reclaimed to the use of man, fields waving with golden harvests, and peaceful dwellings rising by the side of the foaming torrent . for I regard here less the force of the emotion excited, than the relation of the sensations and ideas awakened to that peculiar character of the scene which gives them form and permanence. If I might yield here to the charm of memory, I would dwell on scenes deeply imprinted on my own recol- lection— on the calm of the tropic nights, when the stars, not sparkling, as in our climates, but shining with a steady beam, shed on the gently heaving ocean a mild and planetary radiance; or I would recal those deep wooded valleys of the Cordilleras, where the palms shoot through the leafy roof formed by the thick foliage of other trees, above which their lofty and slender stems appear in lengthened colonnades, " a forest above a forest (l) •" or the Peak of Teneriffe, when a horizontal layer of clouds has separated the cone of cinders from the world beneath, and suddenly the ascending current of the heated air pierces the veil, so that the traveller, standing on the very edge of the crater, sees through the opening the vine-covered slopes of Orotava, and the orange gardens and bananas of the coast. In such scenes it is no longer alone the peaceful charm, of which the face of nature is never wholly destitute, which speaks to our minds, but the peculiar

8 DIFFERENT GRADATIONS OP

character of the landscape, the new and beautiful forms of vegetable life, the grouping of the clouds, and the vague uncertainty with which they mingle with the neighbouring islands, and the distant horizon half visible through the morning mist. All that the senses but partially comprehend, and whatever is most grand and awful in such romantic scenes, open fresh sources of delight. That which sense grasps but imperfectly offers a free field to creative fancy ; the outward impressions change with the changing phases of the mind ; and this without destroying the illusion, by which we imagine ourselves to receive from external nature that with which we have ourselves unconsciously invested her.

When far from our native country, after a long sea voyage, we tread for the first time the lauds of the tropics, we ex- perience an impression of agreeable surprise in recognising, in the cliffs and rocks around, the same forms and sub- stances, similar inclined strata of schistose rocks, the same columnar basalts, which we had left in Europe : this identity, in latitudes so different, reminds us that the solidification of the crust of the earth has been independent of differences of climate. But these schists and these basalts are covered with vegetable forms of new and strange aspect. Amid the luxuriance of this exotic flora, surrounded by colossal forms of unfamiliar grandeur and beauty, we experience (thanks to the marvellous flexibility of our nature) how easily the mind opens to the combination of impressions connected with each other by unperceived links of secret analogy. The imagination recognises in these strange forms nobler deve- opments of those which surrounded our childhood; the colonist loves to give to the plants of his new home names borrowed from his native land, and these strong untaught

THE ENJOYMENT OF NATURE. 9

impressions lead, however vaguely, to the same end as that laborious and extended comparison of facts, by which the philosopher arrives at an intimate persuasion of one indisso- luble chain of affinity binding together all nature.

It may seem a rash attempt to endeavour to analyse into its separate elements the enchantment which the great scenes of nature exert over our minds, for this effect depends espe- cially on the combination and unity of the various emotions and ideas excited ; and yet if we would trace back this power to the objective diversity of the phenomena, we must take a nearer and more discriminating view of individual forms and variously acting forces. The richest and most diversified materials for such an analysis present themselves to the traveller in the landscapes of Southern Asia, in the great Indian Archipelago, and, above all, in those parts of the new continent where the highest summits of the Cordilleras approach the upper surface of the aerial ocean by which our globe is enveloped, and where the subterranean forces which elevated those lofty chains still shake their foundations.

Graphic descriptions of nature, arranged under the guid- ance of leading ideas, are calculated not merely to please the imagination, but also to indicate to us the gradation of those impressions to which I have already alluded, from the uniformity of the sea beach or of the steppes of Siberia, to the rich luxuriance of the torrid zone. If we represent to ourselves Mount Pilatus placed on the Shreckhorn (2), or the Schneekoppe of Silesia on the summit of Mont Blanc, we shall not yet have attained to the height of one of the colossi of the Andes, the Chimborazo, whose height is twice that of Etna ; and we must pile the Eigi or Mount Athos on the Chimborazo, to have an image of the highest summit of

10 DIFFERENT GRADATIONS OF

the Himalaya, the Dhavalagiri. But although the moun- tains of India far surpass in their astonishing elevation (long disputed, but now confirmed by authentic measurements) the Cordilleras of South America, they cannot, from their geographical position, offer that inexhaustible variety of phenomena by which the latter are characterised. The im- pression produced by the grandest scenes of nature does not depend exclusively on height. The chain of the Himalaya is situated far without the torrid zone. Scarcely is a single palm tree (3) found so far north as the beautiful valleys of Kumaoon and Nepaul. In 28° and 34° of latitude, on the southern slope of the ancient Paropamisus, nature no longer displays that abundance of tree ferns, or arbo- rescent grasses, of Heliconias, and of Orchideous plants, which, within the tropics, ascend towards the higher plateaux of the mountains. On the slopes of the Himalaya, under the shade of the Deodar and the large-leaved oak peculiar to these Indian Alps, the rocks of granite and of mica schist are clothed with forms closely resembling those which cha- racterise Europe and Northern Asia ; the species indeed arB not identical, but they are similar in their aspect and phy- siognomy, comprising junipers, alpine birches, gentians, par* nassias, and prickly species of Eibes (4). The chain of the Himalaya is also wanting in those imposing volcanic pheno- mena, which, in the Andes and in the Indian Archipelago, often reveal to the inhabitants, in characters of terror, the existence of forces residing in the interior of our planet. Moreover, on the southern declivity of the Himalaya, where the vapour-loaded atmosphere of Hindostan deposits its moisture, the region of perpetual snow descends to a zone of not more than 11000 or 12000 (11700 or 12800 Eng.)

THE ENJOYMENT OF NATURE. 11

feet of elevation : thus the region of organic life ceases at a limit nearly three thousand feet (5) below that which it reaches in the equinoctial portion of the Cordilleras.

But the mountainous regions which are situated near the equator possess another advantage, to which attention has not been hitherto sufficiently directed. They are that part of our planet in which the contemplation of nature offers in the least space the greatest possible variety of impressions. In the Andes of Cundinamarca, of Quito, and of Peru, fur- rowed by deep barrancas, it is permitted to man to contem- plate all the families of plants and all the stars of the firmament. There, at a single glance, the beholder sees lofty feathered palms, humid forests of bamboos, and all the beau tiful family of Musacese ; and, above these tropic forms, oaks, medlars, wild roses, and umbelliferous plants, as in our Euro- pean homes ; there, too, both the celestial hemispheres are open to his view, and, when night arrives, he sees displayed together the constellation of the Southern Cross, the Mi gollanic clouds, and the guiding stars of the Bear which circle round the Arctic pole. There, the different climates of the earth, and the vegetable forms of which they determine the succession, are placed one over another, stage above stage ; and the laws of the decrement of heat are indelibly written on the rocky walls and the rapid slopes of the Cordilleras, in characters easily legible to the intelligent observer. Not to weary the reader with details of phsenomena which I long since attempted (6) to represent graphically, I will here retrace only a few of the more comprehensive features which, in their com- bination, form those pictures of the torrid zone. That which, in impressions received solely by our senses, partakes of an uncertainty, similar to the effect of the misty atmosphere,

DIFFERENT GRADATIONS OP

waich, in mountain scenery, renders at times every outline dim and indistinct, when scrutinised by reasoning on the cause of the phenomena, may be clearly viewed and correctly resolved into separate elements, to each of which its own individual character is assigned ; and thus, in the study of nature, as well as in its more poetic description, the picture gains in vividness and in objective truth by the well and sharply-marked lines which define individual features.

Not only is the torrid zone, through the abundance and luxuriance of its organic forms, most rich in powerful im- pressions,— it has also another advantage, even greater in reference to the chain of ideas here pursued-, in the uniform regularity which characterises the succession both of meteorological and of organic changes. The well-marked lines of elevation which separate the different forms of vegetable life, seem there to offer to our view the inva- riability of the laws which govern the celestial move- ments, reflected as it were in terrestrial phenomena. Let us dwell for a few moments on the evidences of this regu- larity, which is such, that it can even be measured by scale and number.

In the burning plains which rise but little above the level of the sea, reign the families of Bananas, of Cycadeae, and of Palms, of which the number of species included in our floras of the tropical regions has been so wonderfully augmented in our own days by the labours of botanic travellers. To these succeed, on the slopes of the Cordilleras, in mountain valleys, and in humid and shaded clefts of the rocks, tree ferns raising their thick cylindrical stems, and expanding their delicate foliage, whose lace-like indentations are seen against the deep azure of the sky. There, too, flourishes

THE ENJOYMENT OP NATURE. 13

the Cinchona, whose fever-healing bark is deemed the more salutary the more often the trees are bathed and refreshed by the light mists which form the upper surface of the lowest stratum of clouds. Immediately above the region of forests the ground is covered with white bands of flower- ing social plants, small Aralias, Thibaudias, and myrtle- leaved Andromedas. The Alp rose of the Andes, the mag- nificent Befaria, forms a purple girdle round the spiry peaks. On reaching the cold and stormy regions of the Paramos, shrubs and herbaceous plants, bearing large and richly-coloured blossoms, gradually disappear, and are suc- ceeded by a uniform mantle of monocotyledonous plants. This is the grassy zone, where vast savannahs (on which graze lamas, and cattle descended from those brought from the old world) clothe the high table lands and the wide slopes of the Cordilleras, whence they reflect afar a yellow hue. Trachytic rocks, which pierce the turf, and rise high into those strata of the atmosphere which are supposed to contain a smaller quantity of carbonic acid, support only plants of inferior organization Lichens, Lecideas, and the many-coloured dust of the Lepraria, forming small round patches on the surface of the stone. Scattered islets of fresh-fallen snow arrest the last feeble traces of vegetation, and are succeeded by the region of perpetual snow, of which the lower limit is distinctly marked, and undergoes ex- tremely little change. The elastic subterranean forces strive, for the most part in vain, to break through the snow-clad domes which crown the ridges of the Cordilleras ; but even where these forces have actually opened a permanent channel of communication with the outer air, either through crevices or circular craters, they rarely send forth currents of lava, more

14 DIFFERENT GRADATIONS OF

often erupting ignited scoriae, jets of carbonic acid gas and sulphuretted hydrogen, and hot steam. The contemplation of this grand and imposing spectacle appears to have produced on the minds of the earlier inhabitants of those countries only vague feelings of astonishment and awe. It might have been imagined, that, as we have before said, the well- marked periodic return of the same phenomena, and the uniform manner in which they group themselves in ascending zones, would have rendered easier a knowledge of the laws of nature; but so far as history and tradition enable us to trace, we do not find that the advantages possessed by those favoured regions have been so improved. Recent researches have rendered it very doubtful whether the primitive seat of Hindoo civilisation, one of the most wonderful phases of the rapid progress of mankind, were really within the tropics. Airy ana Vaedjo, the ancient cradle of the Zend, was to the north-west of the Upper Indus ; and after the separation of the Iraunians from the Brahminical institution, it was in a country bounded by the Himalaya and the small Yindhya chain, that the language which had previously been common to the Iraunians and Hindoos, assumed among the latter (together with manners, customs, and the social state), an individual form in the Magadha, or Madliya Desa (7). The extension of the Sanscrit language and civilisation to its south-easternmost limit, far within the torrid zone, has been described by my brother, Wilhelin von Humboldt, in his great work on the Kawi, and other languages of kindred structure (8).

Notwithstanding the greater difficulties with which in more northern climates, the discovery of general laws was surrounded, by the excessive complication of phenomena, aad

THE ENJOYMENT OF NATURE. 15

the perpetual local variations, both in the movements of the atmosphere and in the distribution of organic forms, it was to the inhabitants of the temperate zone that a rational knowledge of physical forces first revealed itself. It is from this northern zone, which has shown itself favourable to the progress of reason, to the softening of manners, and to public liberty, that the germs of civilisation have been imported into the torrid zone, either by the great movements of the migration of races, or by the establishment of colonies, very different in their institution in modern times from those of the Greeks and Phoenicians.

In considering the influences which the order and succes- sion of phsenomena may have exercised on the greater or less facility of recognizing their producing causes, I have indicated that important point in the contact of the human mind with the external world, at which there is added to the charm attendant on the simple contemplation of nature, the enjoy- ment springing from a knowledge of the laws which govern the order and mutual relations of phsenomena. Thenceforth the persuasion of the existence of an harmonious system of fixed laws, which was long the object of a vague intuition, gradually acquires the certainty of a rational truth, and man, as our immortal Schiller Jias said " Amid ceaseless change, seeks the unchanging pole (9)"

In order to reascend to the first germ of this more thoughtful enjoyment, we need only cast a rapid glance on the earliest glimpses of the Philosophy of Nature, or of the ancient doctrine of the Cosmos, We find amongst the most savage nations (and my own travels have confirmed the truth of this assertion), a secret and terror-mingled presenti- ment of the unity of natural forces, blending with the dim voi,. i. D

16 DIFFERENT GRADATIONS OP

perception of an invisible and spiritual essence manifesting itself through these forces, whether in unfolding the flower and perfecting the fruit of the food-bearing tree, or in the subterranean movements which shake the ground, and the tempests which agitate the atmosphere. A bond connecting the outward world of sense with the inward world of thought may be here perceived ; the two become unconsciously con- founded, and the first germ of a philosophy of nature is developed in the mind of man without the firm support of observation. Amongst nations least advanced in civilisa- tion, the imagination delights itself in strange and fantastic creations. A predilection for the figurative influences both ideas and language. Instead of examining, men con tent themselves with conjecturing, dogmatising, and inter- preting supposed facts which have never been observed. The world of ideas and of sentiments does not reflect back the image of the external world in its primitive purity. That which in some regions of the earth, and among a small number of individuals gifted with superior intelligence, mani- fests itself as the rudiment of natural philosophy, appears in other regions and among other races of mankind as the result of mystic tendencies and instinctive intuitions, It is in the intimate communion with external nature, and the deep emotions which it inspires, that we may also trace, in part, the first impulses to the deification and worship ol the destroying and preserving powers of nature. At a later period of human civilisation, when man, having passed through different stages of intellectual development, has arrived at the free enjoyment of the regulating power of reflection, and has learned, as it were by a progressive enfran- chisement, to separate the world of ideas from that of the

THE ENJOYMENT OF NATURE. 17

perceptions of sense, a vague presentiment of the unity of natural forces no longer suffices him. The exercise of thought then begins to accomplish its noble task, and, by observation and reasoning combined, the students of nature strive with ardour to ascend to the causes of phse- nomena.

The history of science teaches us how difficult it has been for this active curiosity always to produce sound fruits. Inexact and incomplete observations have led, through false inductions, to that great number of erroneous physical views which have been perpetuated as popular prejudices among all classes of society. Thus, by the side of a solid and scien- tific knowledge of phsenomena, there has been preserved a system of pretended 'results of observation, the more diffi- cult to shake because it takes no account of any of the facts by which it is overturned. This empiricism melan- choly inheritance of earlier times invariably maintains whatever axioms it has laid down; it is arrogant, as is every thing that is narrow-minded ; wliilst true physical philosophy, founded on science, doubts because it seeks to investigate thoroughly, distinguishes between that which is certain and