In such cases, moreover, the ground of the heavens, as seen between the stars, is for the most part perfectly dark, which again would not be the case if innumerable multitudes of stars, too minute to be individually discernible, existed beyond. In other regions we are presented with the phenomenon of an almost uniform degree of brightness of the individual stars, accompanied with a very even distribution of them over the ground of the heavens, both the larger and smaller magnitudes being strikingly deficient. In such cases it is equally impossible not to perceive that we are looking through a sheet of stars nearly of a size and of no great thickness compared with the distance which separates them from us. Were it otherwise we should be driven to suppose the more distant stars were uniformly the larger, so as to compensate by their intrinsic brightness for their greater distance, a supposition contrary to all probability.
In others again, and that not infrequently, we are presented with a double phenomenon of the same kind—viz., a tissue, as it were, of large stars spread over another of very small ones, the intermediate magnitudes being wanting, and the conclusion here seems equally evident that in such cases we look through two sidereal sheets separated by a starless interval.
Throughout by far the larger portion of the extent of the Milky Way in both hemispheres the general blackness of the ground of the heavens on which its stars are projected, and the absence of that innumerable multitude and excessive crowding of the smallest visible magnitudes, and of glare produced by the aggregate light of multitudes too small to affect the eye singly, which the contrary supposition would appear to necessitate, must, we think, be considered unequivocal indications that its dimensions, in directions where those conditions obtain, are not only not infinite, but that the space-penetrating power of our telescopes suffices fairly to pierce through and beyond it.
It is but right, however, to warn our readers that this conclusion has been controverted, and that by an authority not lightly to be put aside, on the ground of certain views taken by Olbers as to a defect of perfect transparency in the celestial spaces, in virtue of which the light of the more distant stars is enfeebled more than in proportion to their distance. The extinction of light thus originating proceeding in geometrical ratio, while the distance increases in arithmetical, a limit, it is argued, is placed to the space-penetrating power of telescopes far within that which distance alone, apart from such obscuration, would assign.
It must suffice here to observe that the objection alluded to, if applicable to any, is equally so to every part of the galaxy. We are not at liberty to argue that at one part of its circumference our view is limited by this sort of cosmical veil, which extinguishes the smaller magnitudes, cuts off the nebulous light of distant masses, and closes our view in impenetrable darkness; while at another we are compelled, by the clearest evidence telescopes can afford, to believe that star-strewn vistas lie open, exhausting their powers and stretching out beyond their utmost reach, as is proved by that very phenomenon which the existence of such a veil would render impossible—viz., infinite increase of number and diminution of magnitude, terminating in complete irresolvable nebulosity.
Such is, in effect, the spectacle afforded by a very large portion of the Milky Way in that interesting region near its point of bifurcation in Scorpio, where, through the hollows and deep recesses of its complicated structure, we behold what has all the appearance of a wide and indefinitely prolonged area strewed over with discontinuous masses and clouds of stars, which the telescope at last refuses to analyse. Whatever other conclusions we may draw, this must anyhow be regarded as the direction of the greatest linear extension of the ground-plan of the galaxy. And it would appear to follow also that in those regions where that zone is clearly resolved into stars well separated and seen projected on a black ground, and where, by consequence, it is certain, if the foregoing views be correct, that we look out beyond them into space, the smallest visible stars appear as such not by reason of excessive distance, but of inferiority of size or brightness.
III.—Variable, Temporary and Binary Stars
Wherever we can trace the law of periodicity we are strongly impressed with the idea of rotatory or orbitual motion. Among the stars are several which, though in no way distinguishable from others by any apparent change of place, nor by any difference of appearance in telescopes, yet undergo a more or less regular periodical increase and diminution of lustre, involving in one or two cases a complete extinction and revival. These are called periodic stars. The longest known, and one of the most remarkable, is the star Omicron in the constellation Cetus (sometimes called Mira Ceti), which was first noticed as variable by Fabricius in 1596. It appears about twelve times in eleven years, remains at its greatest brightness about a fortnight, being then on some occasions equal to a large star of the second magnitude, decreases during about three months, till it becomes completely invisible to the naked eye, in which state it remains about five months, and continues increasing during the remainder of its period. Such is the general course of its phases. But the mean period above assigned would appear to be subject to a cyclical fluctuation embracing eighty-eight such periods, and having the effect of gradually lengthening and shortening alternately those intervals to the extent of twenty-five days one way and the other. The irregularities in the degree of brightness attained at the maximum are also periodical.
Such irregularities prepare us for other phenomena of stellar variation which have hitherto been reduced to no law of periodicity—the phenomena of temporary stars which have appeared from time to time in different parts of the heavens blazing forth with extraordinary lustre, and after remaining awhile, apparently immovable, have died away and left no trace. In the years 945, 1264, and 1572 brilliant stars appeared in the region of the heavens between Cepheus and Cassiopeia; and we may suspect them, with Goodricke, to be one and the same star with a period of 312, or perhaps 156 years. The appearance of the star of 1572 was so sudden that Tycho Brahe, a celebrated Dutch astronomer, returning one evening from his laboratory to his dwellinghouse, was surprised to find a group of country people gazing at a star which he was sure did not exist half an hour before. This was the star in question. It was then as bright as Sirius, and continued to increase till it surpassed Jupiter when brightest, and was visible at midday. It began to diminish in December of the same year, and in March 1574 had entirely disappeared.
In 1803 it was announced by Sir William Herschel that there exist sidereal systems composed of two stars revolving about each other in regular orbits, and constituting which may be called, to distinguish them from double stars, which are only optically double, binary stars. That which since then has been most assiduously watched, and has offered phenomena of the greatest interest, is gamma Virginis. It is a star of the vulgar third magnitude, and its component individuals are very nearly equal, and, as it would seem, in some slight degree variable. It has been known to consist of two stars since the beginning of the eighteenth century, the distance being then between six and seven seconds, so that any tolerably good telescope would resolve it. When observed by Herschel in 1780 it was 5.66 seconds, and continued to decrease gradually and regularly, till at length, in 1836, the two stars had approached so closely as to appear perfectly round and single under the highest magnifying power which could be applied to most excellent instruments—the great refractor of Pulkowa alone, with a magnifying power of a thousand, continuing to indicate, by the wedge-shaped form of the disc of the star, its composite nature.
By estimating the ratio of its length to its breadth, and measuring the former, M. Struve concludes that at this epoch the distance of the two stars, centre from centre, might be stated at .22 seconds. From that time the star again opened, and is now again a perfectly easily separable star. This very remarkable diminution, and subsequent increase, of distance has been accompanied by a corresponding and equally remarkable increase and subsequent diminution of relative angular motion. Thus in 1783 the apparent angular motion hardly amounted to half a degree per annum; while in 1830 it had decreased to 5 degrees, in 1834 to 20 degrees, in 1835 to 40 degrees, and about the middle of 1836 to upwards of 70 degrees per annum, or at the rate of a degree in five days.
This is in entire conformity with the principles of dynamics, which establish a necessary connection between the angular velocity and the distance, as well in the apparent as in the real orbit of one body revolving about another under the influence of mutual attraction; the former varying inversely as the square of the latter, in both orbits, whatever be the curve described and whatever the law of the attractive force.
It is not with the revolutions of bodies of a planetary or cometary nature round a solar centre that we are concerned; it is that of sun round sun—each perhaps, at least in some binary systems, where the individuals are very remote and their period of revolution very long, accompanied by its train of planets and their satellites, closely shrouded from our view by the splendour of their respective suns, and crowded into a space bearing hardly a greater proportion to the enormous interval which separates them than the distances of the satellites of our planets from their primaries bear to their distances from the sun itself.
A less distinctly characterised subordination would be incompatible with the stability of their systems and with the planetary nature of their orbits. Unless close under the protecting wing of their immediate superior, the sweep of their other sun, in its perihelion passage round their own, might carry them off or whirl them into orbits utterly incompatible with conditions necessary for the existence of their inhabitants.
It is to Sir William Herschel that we owe the most complete analysis of the great variety of those objects which are generally classed as nebulae. The great power of his telescopes disclosed the existence of an immense number of these objects before unknown, and showed them to be distributed over the heavens not by any means uniformly, but with a marked preference to a certain district extending over the northern pole of the galactic circle. In this region, occupying about one-eighth of the surface of the sphere, one-third of the entire nebulous contents of the heavens are situated.
The resolvable nebulae can, of course, only be considered as clusters either too remote, or consisting of stars intrinsically too faint, to affect us by their individual light, unless where two or three happen to be close enough to make a joint impression and give the idea of a point brighter than the rest. They are almost universally round or oval, their loose appendages and irregularities of form being, as it were, extinguished by the distance, and only the general figure of the condensed parts being discernible. It is under the appearance of objects of this character that all the greater globular clusters exhibit themselves in telescopes of insufficient optical power to show them well.
The first impression which Halley and other early discoverers of nebulous objects received from their peculiar aspect was that of a phosphorescent vapour (like the matter of a comet's tail), or a gaseous and, so to speak, elementary form of luminous sidereal matter. Admitting the existence of such a medium, Sir W. Herschel was led to speculate on its gradual subsidence and condensation, by the effect of its own gravity, into more or less regular spherical or spheroidal forms, denser (as they must in that case be) towards the centre.
Assuming that in the progress of this subsidence local centres of condensation subordinate to the general tendency would not be wanting, he conceived that in this way solid nuclei might arise whose local gravitation still further condensing, and so absorbing the nebulous matter each in its immediate neighbourhood, might ultimately become stars, and the whole nebula finally take on the state of a cluster of stars.
Among the multitude of nebulae revealed by his telescope every stage of this process might be considered as displayed to our eyes, and in every modification of form to which the general principle might be conceived to apply. The more or less advanced state of a nebula towards its segregation into discrete stars, and of these stars themselves towards a denser state of aggregation round a central nucleus, would thus be in some sort an indication of age.
ALEXANDER VON HUMBOLDT
Cosmos, a Sketch of the Universe
Frederick Henry Alexander von Humboldt was born in Berlin on September 14, 1769. In 1788 he made the acquaintance of George Forster, one of Captain Cook's companions, and geological excursions made with him were the occasion of his first publications, a book on the nature of basalt. His work in the administration of mines in the principalities of Bayreuth and Anspach furnished materials for a treatise on fossil flora; and in 1827, when he was residing in Paris, he gave to the world his "Voyage to the Equinoctial Regions of the New Continent," which embodies the results of his investigations in South America. Two years later he organised an expedition to Asiatic Russia, charging himself with all the scientific observations. But his principal interest lay in the accomplishment of that physical description of the universe for which all his previous studies had been a preparation, and which during the years 1845 to 1848 appeared under the comprehensive title of "Cosmos, or Sketch of a Physical Description of the Universe." Humboldt died on May 6, 1859.
I.—The Physical Study of the World
The natural world may be opposed to the intellectual, or nature to art taking the latter term in its higher sense as embracing the manifestations of the intellectual power of man; but these distinctions—which are indicated in most cultivated languages—must not be suffered to lead to such a separation of the domain of physics from that of the intellect as would reduce the physics of the universe to a mere assemblage of empirical specialities. Science only begins for man from the moment when his mind lays hold of matter—when he tries to subject the mass accumulated by experience to rational combinations.
Science is mind applied to nature. The external world only exists for us so far as we conceive it within ourselves, and as it shapes itself within us into the form of a contemplation of nature. As intelligence and language, thought and the signs of thought, are united by secret and indissoluble links, so, and almost without our being conscious of it, the external world and our ideas and feelings melt into each other. "External phenomena are translated," as Hegel expresses it in his "Philosophy of History," "in our internal representation of them." The objective world, thought by us, reflected in us, is subjected to the unchanging, necessary, and all-conditioning forms of our intellectual being.
The activity of the mind exerts itself on the elements furnished to it by the perceptions of the senses. Thus, in the youth of nations there manifests itself in the simplest intuition of natural facts, in the first efforts made to comprehend them, the germ of the philosophy of nature.
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 general forces 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 meditation, and of the spirit of the age, which is ever reflected in the operations of the human mind whatever may be their direction.
From the time when man, in interrogating nature, began to experiment or to produce phenomena under definite conditions, and to collect and record the fruits of his 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 character.
The history of science teaches us how 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, side by side with a solid and scientific knowledge of phenomena, there has been preserved a system of pretended results of observation, the more difficult to shake because it takes no account of any of the facts by which it is overturned.
This empiricism—melancholy inheritance of earlier times—invariably maintains whatever axioms it has laid down; it is arrogant, as is everything that is narrow-minded; while true physical philosophy, founded on science, doubts because it seeks to investigate thoroughly—distinguishes between that which is certain and that which is simply probable—and labours incessantly to bring its theories nearer to perfection by extending the circle of observation. This assemblage of incomplete dogmas bequeathed from one century to another, this system of physics made up of popular prejudices, is not only injurious because it perpetuates error with all the obstinacy of ill-observed facts, but also because it hinders the understanding from rising to the level of great views of nature.
Instead of seeking to discover the mean state around which, in the midst of apparent independence and irregularity, the phenomena really and invariably oscillate, this false science delights in multiplying apparent exceptions to the dominion of fixed laws, and seeks, in organic forms and the phenomena of nature, other marvels than those presented by internal progressive development, and by regular order and succession. Ever disinclined to recognise in the present the analogy of the past, it is always disposed to believe the order of nature suspended by perturbations, of which it places the seat, as if by chance, sometimes in the interior of the earth, sometimes in the remote regions of space.
II.—The Inductive Method
The generalisation of laws which were first applied to smaller groups of phenomena advances by successive gradations, and their empire is extended, and their evidence strengthened, so long as the reasoning process is directed to really analogous phenomena. Empirical investigation begins by single perceptions, which are afterwards classed according to their analogy or dissimilarity. Observation is succeeded at a much later epoch by experiment, in which phenomena are made to arise under conditions previously determined on by the experimentalist, guided by preliminary hypotheses, or a more or less just intuition of the connection of natural objects and forces.
The results obtained by observation and experiment lead by the path of induction and analogy to the discovery of empirical laws, and these successive phases in the application of human intellect have marked different epochs in the life of nations. It has been by adhering closely to this inductive path that the great mass of facts has been accumulated which now forms the solid foundation of the natural sciences.
Two forms of abstraction govern the whole of this class of knowledge—viz., the determination of quantitative relations, according to number and magnitude; and relations of quality, embracing the specific properties of heterogeneous matter.
The first of these forms, more accessible to the exercise of thought, belongs to the domain of mathematics; the other, more difficult to seize, and apparently more mysterious, to that of chemistry. In order to submit phenomena to calculation, recourse is had to a hypothetical construction of matter by a combination of molecules and atoms whose number, form, position, and polarity determine, modify, and vary the phenomena.
We are yet very far from the time when a reasonable hope could be entertained of reducing all that is perceived by our senses to the unity of a single principle; but the partial solution of the problem—the tendency towards a general comprehension of the phenomena of the universe—does not the less continue to be the high and enduring aim of all natural investigation.
III.—Distribution of Matter in Space
A physical cosmography, or picture of the universe, should begin, not with the earth, but with the regions of space—the distribution of matter in the universe.
We see matter existing in space partly in the form of rotating and revolving spheroids, differing greatly in density and magnitude, and partly in the form of self-luminous vapour dispersed in shining nebulous spots or patches. The nebulae present themselves to the eye in the form of round, or nebulous discs, of small apparent magnitude, either single or in pairs, which are sometimes connected by a thread of light; when their diameters are greater their forms vary—some are elongated, others have several branches, some are fan-shaped, some annular, the ring being well defined and the interior dark. They are supposed to be undergoing various and progressive changes of form, as condensation proceeds around one or more nuclei in conformity with the laws of gravitation. Between two and three thousand of such unresolvable nebulae have already been counted, and their positions determined.
If we leave the consideration of the attenuated vaporous matter of the immeasurable regions of space, whether existing in a dispersed state as a cosmical ether without form or limits, or in the shape of nebulae, and pass to those portions of the universe which are condensed into solid spheres or spheroids, we approach a class of phenomena exclusively designated as stars or as the sidereal universe. Here, too, we find different degrees of solidity or density in the agglomerated matter.
If we compare the regions of space to one of the island-studded seas of our planet, we may imagine we see matter distributed in groups, whether of unresolvable nebulae of different ages condensed around one or more nuclei, or in clusters of stars, or in stars scattered singly. Our cluster of stars, or the island in space to which we belong, forms a lens-shaped, flattened, and everywhere detached stratum, whose major axis is estimated at seven or eight hundred, and its minor axis at a hundred and fifty times, the distance of Sirius. If we assume that the parallax of Sirius does not exceed that accurately determined for the brightest stars in Centaur (0.9128 sec.), it will follow that light traverses one distance of Sirius in three years, while nine years and a quarter are required for the transmission of the light of the star 61 Cygni, whose considerable proper motion might lead to the inference of great proximity.
Our cluster of stars is a disc of comparatively small thickness divided, at about a third its length, into two branches; we are supposed to be near this division, and nearer to the region of Sirius than to that of the constellation of the Eagle; almost in the middle of the starry stratum in the direction of its thickness.
The place of our solar system and the form of the whole lens are inferred from a kind of scale—i.e., from the different number of stars seen in equal telescopic fields of view. The greater or less number of stars measures the relative depth of the stratum in different directions; giving in each case, like the marks on a sounding-line, the comparative length of visual ray required to reach the bottom; or, more properly, as above and below do not here apply, the outer limit of the sidereal stratum.
In the direction of the major axis, where the greater number of stars are placed behind each other, the remoter ones appear closely crowded together, and, as it were, united by a milky radiance, and present a zone or belt projected on the visible celestial vault. This narrow belt is divided into branches; and its beautiful, but not uniform brightness, is interrupted by some dark places. As seen by us on the apparent concave celestial sphere, it deviates only a few degrees from a great circle, we being near the middle of the entire starry cluster, and almost in the plane of the Milky Way. If out planetary system were far outside the cluster, the Milky Way would appear to telescopic vision as a ring, and at a still greater distance as a resolvable disc-shaped nebula.
IV.—On Earth History
The succession and relative age of different geological formations are traced partly by the order of superposition of sedimentary strata, of metamorphic beds, and of conglomerates, but most securely by the presence of organic remains and their diversities of structure. In the fossiliferous strata are inhumed the remains of the floras and faunas of past ages. As we descend from stratum to stratum to study the relations of superposition, we ascend in the order of time, and new worlds of animal and vegetable existence present themselves to the view.
In our ignorance of the laws under which new organic forms appear from time to time upon the surface of the globe, we employ the expression "new creations" when we desire to refer to the historical phenomena of the variations which have taken place at intervals in the animals and plants that have inhabited the basins of the primitive seas and the uplifted continents.
It has sometimes happened that extinct species have been preserved entire, even to the minutest details of their tissues and articulations. In the lower beds of the Secondary Period, the lias of Lyme Regis, a sepia has been found so wonderfully preserved that a part of the black fluid with which the animal was provided myriads of years ago to conceal itself from its enemies has actually served at the present time to draw its picture. In other cases such traces alone remain as the impression which the feet of animals have left on wet sand or mud over which they passed when alive, or the remains of their undigested food (coprolites).
The analytical study of the animal and vegetable kingdoms of the primitive world has given rise to two distinct branches of science; one purely morphological, which occupies itself in natural and physiological descriptions, and in the endeavour to fill up from extinct forms the chasms which present themselves in the series of existing species; the other branch, more especially geological considers the relations of the fossil remains to the superposition and relative age of the sedimentary beds in which they are found. The first long predominated; and the superficial manner which then prevailed of comparing fossil and existing species led to errors of which traces still remain in the strange denominations which were given to certain natural objects. Writers attempted to identify all extinct forms with living species, as, in the sixteenth century, the animals of the New World were confounded by false analogies with those of the Old.
In studying the relative age of fossils by the order of superposition of the strata in which they are found, important relations have been discovered between families and species (the latter always few in numbers) which have disappeared and those which are still living. All observations concur in showing that the fossil floras and faunas differ from the present animal and vegetable forms the more widely in proportion as the sedimentary beds to which they belong are lower, or more ancient.
Thus great variations have successively taken place in the general types of organic life, and these grand phenomena, which were first pointed out by Cuvier, offer numerical relations which Deshayes and Lyell have made the object of researches by which they have been conducted to important results, especially as regards the numerous and well-preserved fossils of the Tertiary formation. Agassiz, who has examined 1,700 species of fossil fishes, and who estimates at 8,000 the number of living species which have been described, or which are preserved in our collections, affirms that, with the exception of one small fossil fish peculiar to the argillaceous geodes of Greenland, he has never met in the Transition, Secondary, or Tertiary strata with any example of this class specifically identical with any living fish; and he adds the important remark that even in the lower Tertiary formations a third of the fossil fishes of the calcaire grossier and of the London clay belong to extinct families.
We have seen that fishes, which are the oldest vertebrates, first appear in the Silurian strata, and are found in all the succeeding formations up to the birds of the Tertiary Period. Reptiles begin in like manner in the magnesian limestone, and if we now add that the first mammalia are met with in Oolite, the Stonefield slate; and that the first remains of birds have been found in the deposits of the cretaceous period, we shall have indicated the inferior limits, according to our present knowledge, of the four great divisions of the vertebrates.
In regard to invertebrate animals, we find corals and some shells associated in the oldest formations with very highly organised cephalopodes and crustaceans, so that widely different orders of this part of the animal kingdom appear intermingled; there are, nevertheless, many isolated groups belonging to the same order in which determinate laws are discoverable. Whole mountains are sometimes found to consist of a single species of fossil goniatites, trilobites, or nummulites.
Where different genera are intermingled, there often exists a systematic relation between the series of organic forms and the superposition of the formations; and it has been remarked that the association of certain families and species follows a regular law in the superimposed strata of which the whole constitutes one formation. It has been found that the waters in the most distant parts of the globe were inhabited at the same epochs by testaceous animals corresponding, at least in generic character, with European fossils.
Strata defined by their fossil contents, or by the fragments of other rocks which they include, form a geological horizon by which the geologist may recognise his position, and obtain safe conclusions in regard to the identity or relative antiquity of formations, the periodical repetition of certain strata—their parallelism—or their entire suppression. If we would thus comprehend in its greatest simplicity the general type of the sedentary formations, we find in proceeding successively from below upwards: (1) The Transition group, including the Silurian and Devonian (Old Red Sandstone) systems; (2) the Lower Trias, comprising mountain limestone, the coal measures, the lower new red sandstone, and the magnesian limestone; (3) the Upper Trias, composing the bunter, or variegated sandstone, the muschelkalk, and the Keuper sandstone; (4) the Oolitic, or Jurassic series, including Lias; (5) the Cretaceous series; (6) the Tertiary group, as represented in its three stages by the calcaire grossier and other beds of the Paris basin, the lignites, or brown coal of Germany, and the sub-Apennine group of Italy.
To these succeed transported soils (alluvium), containing the gigantic bones of ancient mammalia, such as the mastodons, the dinotherium, and the megatheroid animals, among which is the mylodon of Owen, an animal upwards of eleven feet in length, allied to the sloth. Associated with these extinct species are found the fossil remains of animals still living: elephants, rhinoceroses, oxen, horses, and deer. Near Bogota, at an elevation of 8,200 French feet above the level of the sea, there is a field filled with the bones of mastodon (Campo de Gigantes), in which I have had careful excavations made. The bones found on the table-lands of Mexico belong to the true elephants of extinct species. The minor range of the Himalaya, the Sewalik hills, contain, besides numerous mastodons, the sivatherium and the gigantic land-tortoise (Colossochelys), more than twelve feet in length and six in height, as well as remains belonging to still existing species of elephants, rhinoceroses, and giraffes. It is worthy of notice that these fossils are found in a zone which enjoys the tropical climate supposed to have prevailed at the period of the mastodons.
V.—The Permanence of Science
It has sometimes been regarded as a discouraging consideration that, while works of literature being fast-rooted in 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.
Let 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, 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, while others will become known.
The Theory of the Earth
James Hutton, the notable Scotch geologist, was born at Edinburgh on June 3, 1726. In 1743 he was apprenticed to a Writer to the Signet; but his apprenticeship was of short duration and in the following year he began to study medicine at Edinburgh University, and in 1749 graduated as an M.D. Later he determined to study agriculture, and went, in 1752, to live with a Norfolk farmer to learn practical farming. He did not devote himself entirely to agriculture, but gave a considerable amount of his time to chemical and geological researches. His geological researches culminated in his great work, "The Theory of the Earth," published at Edinburgh in 1795. In this work he propounds the theory that the present continents have been formed at the bottom of the sea by the precipitation of the detritus of former continents, and that the precipitate had been hardened by heat and elevated above the sea by the expansive power of heat. He died on March 26, 1797. Other works are his "Theory of Rain," "Elements of Agriculture," "Natural Philosophy," and "Nature of Coal."
I.—Origin and Consolidation of the Land
The solid surface of the earth is mainly composed of gravel, of calcareous, and argillaceous strata. Sand is separated by streams and currents, gravel is formed by the attrition of stones agitated in water, and argillaceous strata are deposited by water containing argillaceous material. Accordingly, the solid earth would seem to have been mainly produced by water, wind, and tides, and this theory is confirmed by the discovery that all the masses of marble and limestone are composed of the calcareous matter of marine bodies. All these materials were, in the first place, deposited at the bottom of the sea, and we have to consider, firstly, how they were consolidated; and secondly, how they came to be dry land, elevated above the sea.
It is plain that consolidation may have been effected either through the concretion of substances dissolved in water or through fusion by fire. Consolidation through the concretion of substances dissolved in the sea is unlikely, for, in the first place, there are strata, such as siliceous matter, which are insoluble, and which could not therefore have been in solution; and, in the second place, the appearance of the strata is contrary to this supposition. Consolidation was probably effected by heat and fusion. All the substances in the earth may be rendered fluid by heat, and all the appearances in the earth's crust are consistent with the consolidation and crystallisation of fused substances. Not only so, but we find rents and separations and veins in the strata, such as would naturally occur in strata consolidated by the cooling of fused masses, and other phenomena pointing to fusion by heat. We may conclude, then, that all the solid strata of the globe have been hardened from a state of fusion.
But how were these strata raised up from the bottom of the sea and transformed into dry land? Even as heat was the consolidating power, so heat was also probably the elevating power. The power of heat for the expansion of bodies is, as we know, unlimited, and the expansive power of heat was certainly competent to raise the strata above the sea. Heat was certainly competent, and if we examine the crust of the earth we find evidence that heat was used.
If the strata cemented by the heat of fusion were created by the expansive power of heat acting from below, we should expect to find every species of fracture, dislocation, and contortion in those bodies, and every degree of departure from a horizontal towards a vertical position. And this is just what we do find. From horizontal, the strata are frequently found vertical; from continuous, broken, and separated in every possible direction; and from a plane, bent and doubled. The theory is confirmed by an examination of the veins and fissures of the earth which contain matter foreign to the strata they traverse, and evidently forced into them as a fluid under great pressure. Active volcanoes, and extinct volcanoes, and the marks everywhere of volcanic action likewise support the theory of expansion and elevation by heat. A volcano is not made on purpose to frighten superstitious people into fits of piety and devotion; it is to be considered as a spiracle of a subterranean furnace.
Such being the manner of the formation of the crust of the world, can we form any judgment of its duration and durability? If we could measure the rate of the attrition of the present continents, we might estimate the duration of the older continents whose attrition supplied the material for the present dry land. But as we cannot measure the wearing-away of the land, we can merely state generally, first, that the present dry land required an indefinitely long period for its formation; second, that the previous dry land which supplied material for its formation required equal time to make; third, that there is at present land forming at the bottom of the sea which in time will appear above the surface; fourth, that we find no vestige of a beginning, or of an end.
Granite has in its own nature no claim to originality, for it is found to vary greatly in its composition. But, further, it is certain that granite, or a species of the same kind of stone, is found stratified. It is the granit feuilletee of M. de Sauffure, and, if I mistake not, is called gneiss by the Germans. Granite being thus found stratified, the masses of this stone cannot be allowed to any right of priority over the schistus, its companion in Alpine countries.
Lack of stratification, then, cannot be considered a proof of primitive rock. Nor can lack of organized bodies, such as shells, in these rocks, be considered a proof; for the traces of organized bodies may be obliterated by the many subsequent operations of the mineral region. In any case, signs of organized bodies are sometimes found in "primitive" mountains.
Nor can metallic veins, found plentifully in "primitive" mountains, prove anything, for mineral veins are found in various strata.
We maintain that all the land was produced from fused substances elevated from the bottom of the sea. But we do not hold that all parts of the earth have undergone exactly similar and simultaneous vicissitudes; and in respect to the changes which various parts of the land have undergone we may distinguish between primary and secondary strata. Nothing is more certain than that there have been several repeated operations of the mineralising power exerted upon the strata in particular places, and all those mineral operations tend to consolidation. It is quite possible that "primitive" masses which differ from the ordinary strata of the globe have been twice subjected to mineral operations, having been first consolidated and raised as land, and then submerged in order to be again fused and elevated.
II.—The Nature of Mineral Coal
Mineral, or fossil, coal is a species of stratum distinguished by its inflammable and combustible nature. We find that it differs in respect to its purity, and also in respect to its inflammability. As is well known, some coals have almost no earthy ash, some a great deal; and, again, some coals burn with much smoke and fire, while others burn like coke. Where, then, did coal come from, and how can we account for its different species?
A substance proper for the formation of coaly matter is found in vegetable bodies. But how did it become mixed with earthy matter?
Vegetable bodies may be resolved into bituminous or coaly matter either by means of fire or by means of water. Both may be used by nature in the formation of coal.
By the force of subterranean heat vegetable matter may have been charred at the bottom of the sea, and the oleaginous, bituminous, and fuliginous substances diffused through the sea as a result of the burning may have been deposited at the bottom of the sea as coal. Further, the bituminous matter from the smoke of vegetable substances burned on land would ultimately be deposited from the atmosphere and settle at the bottom of the sea.
Many of the rivers contain in solution an immense quantity of inflammable vegetable substance, and this is carried into the sea, and precipitated there.
From these two sources, then, the sea gets bituminous material, and this material, condensed and consolidated by compression and by heat, at the bottom of the sea, would form a black body of a most uniform structure, breaking with a polished surface, and burning with more or less smoke or flame in proportion as it be distilled less or more by subterranean heat. And such a body exactly represents our purest fossil coal, which gives the most heat and leaves the least ash.
In some cases the bituminous material in suspension in the sea would be mixed more or less with argillaceous, calcareous, and other earthy substances; and these being precipitated along with the bituminous matter would form layers of impure coal with a considerable amount of ash.
But there is still a third source of coal. Vegetable bodies macerated in water, and consolidated by compression, form a body almost indistinguishable from some species of coal, as is seen in peat compressed under a great load of earth; and there can be no doubt that coal sometimes originates in this way, for much fossil coal shows abundance of vegetable bodies in its composition.
There remains only to consider the change in the disposition of coal strata. Coal strata, which had been originally in a horizontal position, are now found sometimes standing erect, even perpendicular. This, also, is consistent with our theory of the earth. Indeed, there is not a substance in the mineral kingdom in which the action of subterranean heat is better shown. These strata are evidently a deposit of inflammable substances which all come originally from vegetable bodies. In this stage of their formation they must all contain volatile oleaginous constituents. But some coal strata contain no volatile constituents, and the disappearance of the volatile oleaginous substances must have been produced by distillation, proceeding perhaps under the restraining force of immense compression.
We cannot doubt that such distillation does take place in the mineral regions, when we consider that in most places of the earth we find the evident effects of such distillation in the naphtha and petroleum that are constantly emitted along with water in certain springs. We have, therefore, sufficient proof of this operation of distillation.
III.—The Disintegration and Dissolution of Land
Whether we examine the mountain or the plain, whether we consider the disintegration of the rocks or the softer strata of the earth, whether we regard the shores of seas or the central plains of continents, whether we contemplate fertile lands or deserts, we find evidence of a general dissolution and decay of the solid surface of the globe. Every great river and deep valley gives evidence of the attrition of the land. The purpose of the dry land is to sustain a system of plants and animals; and for this purpose a soil is required, and to make a soil the solid strata must be crumbled down. The earth is nothing more than an indefinite number of soils and situations suitable for various animals and plants, and it must consist of both solid rock and tender earth, of both moist and dry districts; for all these are requisite for the world we inhabit.
But not only is the solid rock crumbling into soil by the action of air and water, but the soil gradually progresses towards the sea, and sooner or later the sea must swallow up the land. Vegetation and masses of solid rock retard the seaward flow of the soil; but they merely retard, they cannot wholly prevent. In proportion as the mountains are diminished, the haugh, or plain, between them grows more wide, and also on a lower level; but while there is a river running on a plain, and floods produced in the seasons of rain, there is nothing stable in the constitution of the surface of the land.
The theory of the earth which I propound is founded upon the great catastrophes that can happen to the earth. It supposes strata raised from the bottom of the sea and elevated into mountainous continents. But, between the catastrophes, it requires nothing further than the ordinary everyday effects of air and water. Every shower of rain, every stream, participates in the dissolution of the land, and helps to transport to the sea the material for future continents.
The prodigious waste of the land we see in places has seemed to some to require some other explanation; but I maintain that the natural operations of air and water would suffice in time to produce the effects observed. It is true that the wastage would be slow; but slow destruction of rock with gradual formation of soil is just what is required in the economy of nature. A world sustaining plants and animals requires continents which endure for more than a day.
If this continent of land, first collected in the sea, is to remain a habitable earth, and to resist the moving waters of the globe, certain degrees of solidity or consolidation must be given to that collection of loose materials; and certain degrees of hardness must be given to bodies which are soft and incoherent, and consequently so extremely perishable in the situation in which they are now placed.
But, at the same time that this earth must have solidity and hardness to resist the sudden changes which its moving fluids would occasion, it must be made subject to decay and waste upon the surface exposed to the atmosphere; for such an earth as were made incapable of change, or not subject to decay, would not afford that fertile soil which is required in the system of this world—a soil on which depends the growth of plants and life of animals—the end of its intention.
Now, we find this earth endued precisely with such degree of hardness and consolidation as qualifies it at the same time to be a fruitful earth, and to maintain its station with all the permanency compatible with the nature of things, which are not formed to remain unchangeable.
Thus we have a view of the most perfect wisdom in the contrivance of that constitution by which the earth is made to answer, in the best manner possible, the purpose of its intention, that is, to maintain and perpetuate a system of vegetation, or the various races of useful plants, or a system of living animals, which are in their turn subservient to a system still infinitely more important—I mean a system of intellect. Without fertility in the earth, many races of plants and animals would soon perish, or be extinct; and with permanency in our land it were impossible for the various tribes of plants and animals to be dispersed over the surface of a changing earth. The fact is that fertility, adequate to the various ends in view, is found in all the quarters of the world, or in every country of the earth; and the permanency of our land is such as to make it appear unalterable to mankind in general and even to impose upon men of science, who have endeavoured to persuade us that this earth is not to change.
Nothing but supreme power and wisdom could have reconciled those two opposite ends of intention, so as both to be equally pursued in the system of nature, and so equally attained as to be imperceptible to common observation, and at the same time a proper object of the human understanding.
Jean Baptiste de Monet, Chevalier de Lamarck, was born in Picardy, France, Aug. I, 1744, the cadet of an ancient but impoverished house. It was his father's desire that he should enter the Church, but his inclination was for a military life; and having, at the age of seventeen, joined the French army under De Broglie, he had within twenty-four hours the good fortune so to distinguish himself as to win his commission. When the Museum of Natural History was brought into existence in 1794 he was sufficiently well-known as a naturalist to be entrusted with the care of the collections of invertebrates, comprising insects, molluscs, polyps, and worms. Here he continued to lecture until his death in 1829. Haeckel, classifying him in the front rank with Goethe and Darwin, attributes to him "the imperishable glory of having been the first to raise the theory of descent to the rank of an independent scientific theory." The form of his theory was announced in 1801, but was not given in detail to the world until 1809, by the publication of his "Zoological Philosophy" ("Philosophie Zoologique"). The Lamarckian theory of the hereditary transmission of characters acquired by use, disuse, etc., has still a following, though it is controverted by the schools of Darwin and Weissmann. Lamarck died on December 18, 1829.
I.—The Ladder of Life
If we look backwards down the ladder of animal forms we find a progressive degradation in the organisation of the creatures comprised; the organisation of their bodies becomes simpler, the number of their faculties less. This well-recognised fact throws a light upon the order in which nature has produced the animals; but it leaves unexplained the fact that this gradation, though sustained, is irregular. The reason will become clear if we consider the effects produced by the infinite diversity of conditions in different parts of the globe upon the general form, the limbs, and the very organisation of the animals in question.
It will, in fact, be evident that the state in which we find all animals is the product, on the one hand, of the growing composition of the organisation which tends to form a regular gradation; and that, for the rest, it results from a multitude of circumstances which tend continually to destroy the regularity of the gradation in the increasingly composite nature of the organism.
Not that circumstances can effect any modification directly. But changed circumstances produce changed wants, changed wants changed actions. If the new wants become constant the animals acquire new habits, which are no less constant than the wants which gave rise to them. And such new habits will necessitate the use of one member rather than another, or even the cessation of the use of a member which has lost its utility.
We will look at some familiar examples of either case. Among vegetables, which have no actions, and therefore no habits properly so called, great differences in the development of the parts do none the less arise as a consequence of changed circumstances; and these differences cause the development of certain of them, while they attenuate others and cause them to disappear. But all this is caused by changes in the nutrition of the plant, in its absorptions and transpirations, in the quantity of heat and light, of air and moisture, which it habitually receives; and, lastly, by the superiority which certain of its vital movements may assert over the others. There may arise between individuals of the same species, of which some are placed in favourable, others amid unfavourable, conditions, a difference which by degrees becomes very notable.
Suppose that circumstances keep certain individuals in an ill-nourished or languid state. Their internal organisation will at length be modified, and these individuals will engender offspring which will perpetuate the modifications thus acquired, and thus will in the end give place to a race quite distinct from that of which the individual members come together always under circumstances favourable to their development.
For instance, if a seed of some meadow flower is carried to dry and stony ground, where it is exposed to the winds and there germinates, the consequence will be that the plant and its immediate offspring, being always ill-nourished, will give rise to a race really different from that which lives in the field; yet this, none the less, will be its progenitor. The individuals of this race will be dwarfed; and their organs, some being increased at the expense of the rest, will show distinctive proportions. What nature does in a long time we do every day ourselves. Every botanist knows that the vegetables transplanted to our gardens out of their native soil undergo such changes as render them at last unrecognisable.
Consider, again, the varieties among our domestic fowls and pigeons, all of them brought into existence by being raised in diverse circumstances and different countries, and such as might be sought in vain in a state of nature. It is matter of common knowledge that if we raise a bird in a cage, and keep it there for five or six years, it will be unable to fly if restored to liberty. There has, indeed, been no change as yet in the form of its members; but if for a long series of generations individuals of the same race had been kept caged for a considerable time, there is no room for doubt that the very form of their limbs would little by little have undergone notable alteration. Much more would this be the case if their captivity had been accompanied by a marked change of climate, and if these individuals had by degrees accustomed themselves to other sorts of food and to other measures for acquiring it. Such circumstances, taken constantly together, would have formed insensibly a new and clearly denned race.
The following example shows, in regard to plants, how the change of some important circumstance may tend to change the various parts of these living bodies.
So long as the ranunculus aquatilis, the water buttercup, is under water its leaves are all finely indented, and the divisions are furnished with capillaries; but as soon as the stalk of the plant reaches the surface the leaves, which develop in the air, are broadened out, rounded, and simply lobed. If the plant manages to spring up in a soil that is merely moist, and not covered with water, the stems will be short, and none of the leaves will show these indentations and capillaries. You have then the ranunculus hederaceus, which botanists regard as a distinct species.
Among animals changes take place more slowly, and it is therefore more difficult to determine their cause. The strongest influence, no doubt, is that of environment. Places far apart are different, and—which is too commonly ignored—a given place changes its climate and quality with time, though so slowly in respect of human life that we attribute to it perfect stability. Hence it arises that we have not only extreme changes, but also shadowy ones between the extremes.
Everywhere the order of things changes so gradually that man cannot observe the change directly, and the animal tribes in every place preserve their habits for a long time; whence arises the apparent constancy of what we call species—a constancy which has given birth in us to the idea that these races are as old as nature.
But the surface of the habitable globe varies in nature, situation, and climate, in every variety of degrees. The naturalist will perceive that just in proportion as the environment is notably changed will the species change their characters.
It must always be recognised:
(1) That every considerable and constant change in the environment of a race of animals works a real change in their wants.
(2) That every change in their wants necessitates new actions to supply them, and consequently new habits.
(3) That every new want calling for new actions for its satisfaction affects the animal in one of two ways. Either it has to make more frequent use of some particular member, and this will develop the part and cause it to increase in size; or it must employ new members which will grow in the animal insensibly in response to the inward yearning to satisfy these wants. And this I will presently prove from known facts.
How the new wants have been able to attain satisfaction, and how the new habits have been acquired, it will be easy to see if regard be had to the two following laws, which observation has always confirmed.
FIRST LAW.—In every animal which has not arrived at the term of its developments, the more frequent and sustained use of any organ strengthens, develops, and enlarges that organ, and gives it a power commensurate with the duration of this employment of it. On the other hand, constant disuse of such organ weakens it by degrees, causes it to deteriorate, and progressively diminishes its faculties, so that in the end it disappears.
SECOND LAW.—All qualities naturally acquired by individuals as the result of circumstances to which their race is exposed for a considerable time, or as a consequence of a predominant employment or the disuse of a certain organ, nature preserves to individual offspring; provided that the acquired modifications are common to the two sexes, or, at least, to both parents of the individual offspring.
Naturalists have observed that the members of animals are adapted to their use, and thence have concluded hitherto that the formation of the members has led to their appropriate employment. Now, this is an error. For observation plainly shows that, on the contrary, the development of the members has been caused by their need and use; that these have caused them to come into existence where they were wanting.
But let us examine the facts which bear upon the effects of employment or disuse of organs resulting from the habits which a race has been compelled to form.
II.—The Penalties of Disuse
Permanent disuse of an organ as a consequence of acquired habits gradually impoverishes it, and in the end causes it to disappear, or even annihilates it altogether.
Thus vertebrates, which, in spite of innumerable particular distinctions, are alike in the plan of their organisation, are generally armed with teeth. Yet those of them which by circumstances have acquired the habit of swallowing their prey without mastication have been liable to leave their teeth undeveloped. Consequently, the teeth have either remained hidden between the bony plates of the jaws, or have even been, in the course of time, annihilated.
The whale was supposed to have no teeth at all till M. Geoffrey found them hidden in the jaws of the foetus. He has also found in birds the groove in which teeth might be placed, but without any trace of the teeth themselves. A similar case to that of the whale is the ant-eater (nyomecophaga), which has long given up the practice of mastication.
Eyes in the head are an essential part of the organisation of vertebrates. Yet the mole, which habitually makes no use of the sense of sight, has eyes so small that they can hardly be seen; and the aspalax, whose habits-resemble a mole's, has totally lost its sight, and shows but vestiges of eyes. So also the proteus, which inhabits dark caves under water.
In such cases, since the animals in question belong to a type of which eyes are an essential part, it is clear that the impoverishment, and even the total disappearance, of these organs are the results of long continued disuse.
With hearing, the case is otherwise. Sound traverses everything. Therefore, wherever an animal dwells it may exercise this faculty. And so no vertebrate lacks it, and we never find it re-appearing in any of the lower ranges. Sight disappears, re-appears, and disappears again, according as circumstances deny or permit its exercise.
Four legs attached to its skeleton are part of the reptile type; and serpents, particularly as between them and the fishes come the batrachians—frogs, etc.—ought to have four legs.
But serpents, having acquired the habit of gliding along the ground, and concealing themselves amid the grass, their bodies, as a consequence of constantly repeated efforts to lengthen themselves out in order to pass through narrow passages, have acquired considerable length of body which is out of all proportion to their breadth.
Now, feet would have been useless to these animals, and consequently would have remained unemployed; for long legs would have interfered with their desire to go on their bellies; and short legs, being limited in number to four, would have been incapable of moving their bodies. Thus total disuse among these races of animals has caused the parts which have fallen into disuse totally to disappear.
Many insects, which by their order and genus should have wings, lack them more or less completely for similar reasons.
III.—The Advantages of Use
The frequent use of an organ, if constant and habitual, increases its powers, develops it, and makes it acquire dimensions and potency such as are not found among animals which use it less.
Of this principle, the web-feet of some birds, the long legs and neck of the stork, are examples. Similarly, the elongated tongue of the ant-eater, and those of lizards and serpents.
Such wants, and the sustained efforts to satisfy them, have also resulted in the displacement of organs. Fishes which swim habitually in great masses of water, since they need to see right and left of them, have the eyes one upon either side of the head. Their bodies, more or less flat, according to species, have their edges perpendicular to the plane of the water; and their eyes are so placed as to be one on either side of the flattened body. But those whose habits bring them constantly to the banks, especially sloping banks, have been obliged to lie over upon the flattened surface in order to approach more nearly. In this position, in which more light falls on the upper than on the under surface, and their attention is more particularly fixed upon what is going on above than on what is going on below them, this want has forced one of the eyes to undergo a kind of displacement, and to keep the strange position which it occupies in the head of a sole or a turbot. The situation is not symmetrical because the mutation is not complete. In the case of the skate, however, it is complete; for in these fish the transverse flattening of the body is quite horizontal, no less than that of the head. And so the eyes of a skate are not only placed both of them on the upper surface, but have become symmetrical.
Serpents need principally to see things above them, and, in response to this need, the eyes are placed so high up at the sides of the head that they can see easily what is above them on either side, while they can see in front of them but a very little distance. To compensate for this, the tongue, with which they test bodies in their line of march, has been rendered by this habit thin, long, and very contractile, and even, in most species, has been split so as to be able to test more than one object at a time. The same custom has resulted similarly in the formation of an opening at the end of the muzzle by which the tongue may be protruded without any necessity for the opening of the jaws.
The effect of use is curiously illustrated in the form and figure of the giraffe. This animal, the largest of mammals, is found in the interior of Africa, where the ground is scorched and destitute of grass, and has to browse on the foliage of trees. From the continual stretching thus necessitated over a great space of time in all the individuals of the race, it has resulted that the fore legs have become longer than the hind legs, and that the neck has become so elongated that the giraffe, without standing on its hind legs, can raise its head to a height of nearly twenty feet. Observation of all animals will furnish similar examples.
None, perhaps, is more striking than that of the kangaroo. This animal, which carries its young in an abdominal pouch, has acquired the habit of carrying itself upright upon its hind legs and tail, and of moving from place to place in a series of leaps, during which, in order not to hurt its little ones, it preserves its upright posture. Observe the result.
(1) Its front limbs, which it uses very little, resting on them only in the instant during which it quits its erect posture, have never acquired a development in proportion to the other parts; they have remained thin, little, and weak.
(2) The hind legs, almost continually in action, whether to bear the weight of the whole body or to execute its leaps, have, on the contrary, obtained a considerable development; they are very big and very strong.
(3) Finally, the tail, which we observe to be actively employed, both to support the animal's weight and to execute its principal movements, has acquired at its base a thickness and a strength that are extremely remarkable.
When the will determines an animal to a certain action, the organs concerned are forthwith stimulated by a flow of subtle fluids, which are the determining cause of organic changes and developments. And multiplied repetitions of such acts strengthen, extend, and even call into being the organs necessary to them. Now, every change in an organ which has been acquired by habitual use sufficient to originate it is reproduced in the offspring if it is common to both the individuals which have come together for the reproduction of their species. In the end, this change is propagated and passes to all the individuals which come after and are submitted to the same conditions, without its being necessary that they should acquire it in the original manner.
For the rest, in the union of disparate couples, the disparity is necessarily opposed to the constant propagation of such qualities and outward forms. This is why man, who is exposed to such diversity of conditions, does not preserve and propagate the qualities or the accidental defects which he has been in the way of acquiring. Such peculiarities will be produced only in case two individuals who share them unite; these will produce offspring bearing similar characteristics, and, if successive generations restrict themselves to similar unions, a distinct race will then be formed. But perpetual intermixture will cause all characters acquired through particular circumstances to disappear. If it were not for the distances which separate the races of men, such intermixture would quickly obliterate all national distinctions.
Here, then, is the conclusion to which we have come. It is a fact that every genus and species of animal has its characteristic habits combined with an organisation perfectly in harmony with them. From the consideration of this fact one of two conclusions must follow, and that though neither of them can be proved.
(1) The conclusion admitted hitherto—that nature (or its Author) in creating the animals has foreseen all the possible sets of circumstances in which they would have to live, has given to each species a constant organisation, and has shaped its parts in a determined and invariable way so that every species is compelled to live in the districts and the climates where it is actually formed, and to keep the habits by which it is actually known.
(2) My own conclusion—that nature has produced in succession all the animal species, beginning with the more imperfect, or the simpler, and ending with the more perfect; that in so doing it has gradually complicated their organisation; and that of these animals, dispersed over the habitable globe, every species has acquired, under the influence of the circumstances amid which it is found, the habits and modifications of form which we associate with it.
To prove that the second of these hypotheses is unfounded, it will be necessary, first, to prove that the surface of the globe never varies in character, in exposure, situation, whether elevated or sheltered, climate, etc.; and, secondly, to prove that no part of the animal world undergoes, even in the course of long periods of time, any modification through change of circumstances, or as a consequence of a changed manner of life and action.
Now, a single fact which establishes that an animal, after a long period of domestication, differs from the wild stock from which it derives, and that among the various domesticated members of a species may be found differences no less marked between individuals which, have been subjected to one use and those which have been subjected to another, makes it certain that the former conclusion is not consistent with the laws of nature, and that the second is.
Everything, therefore, concurs to prove my assertion, to wit—that it is not form, whether of the body or of the parts, which gives rise to the habits of animals and their manner of life; but that, on the contrary, in the habits, the manner of living, and all the other circumstances of environment, we have those things which in the course of time have built up animal bodies with all their members. With new forms new faculties have been acquired, and little by little nature has come to shape animals and all living things in their present forms.
Johann Caspar Lavater, the Swiss theologian, poet, and physiognomist, was born at Zuerich on November 15, 1741. He began his public life at the age of twenty-one as a political reformer. Five years later he appeared as a poet, and published a volume of poetry which was very favourably received. During the next five years he produced a religious work, which was considered heretical, although its mystic, religious enthusiasm appealed to a considerable audience. His fame, however, rests neither on his poetry nor on his theology, but on his physiognomical studies, published in four volumes between 1775-78 under the title "Physiognomical Fragments for the Advancement of Human Knowledge and Human Life" ("Physiognomische Fragmente zur Befoerderung des Menschenkenntniss und Menschenliebe"). The book is diffuse and inconsequent, but it contains many shrewd observations with respect to physiognomy and has had no little influence on popular opinion in this matter. Lavater died on January 2, 1801.
I.—The Truth of Physiognomy
There can be no doubt of the truth of physiognomy. All countenances, all forms, all created beings, are not only different from each other in their classes, races, kinds, but are also individually distinct. It is indisputable that all men estimate all things whatever by their external temporary superficies—that is to say, by their physiognomy. Is not all nature physiognomy, superficies and contents, body and spirit, external effect and internal power? There is not a man who does not judge of all things that pass through his hands by their physiognomy—there is not a man who does not more or less, the first time he is in company with a stranger, observe, estimate, compare, judge him according to appearances. When each apple, each apricot, has a physiognomy peculiar to itself, shall man, the lord of the earth, have none?
Man is the most perfect of all earthly creatures. In no other creature are so wonderfully united the animal, the intellectual, and the moral. And man's organisation peculiarly distinguishes him from all other beings, and shows him to be infinitely superior to all those other visible organisms by which he is surrounded. His head, especially his face, convinces the accurate observer, who is capable of investigating truth, of the greatness and superiority of his intellectual qualities. The eye, the expression, the cheeks, the mouth, the forehead, whether considered in a state of entire rest, or during their innumerable varieties of motion—in fine, whatever is understood by physiognomy—are the most expressive, the most convincing picture of interior sensations, desires, passions, will, and of all those properties which so much exalt moral above animal life.
Although the physiological, intellectual, and moral are united in man, yet it is plain that each of these has its peculiar station where it more especially unfolds itself and acts.
It is, beyond contradiction, evident that, though physiological or animal life displays itself through all the body, and especially through all the animal parts, yet it acts more conspicuously in the arm, from the shoulder to the ends of the fingers.
It is not less evident that intellectual life, or the powers of the understanding and the mind, make themselves most apparent in the circumference and form of the solid parts of the head, especially the forehead; though they will discover themselves to the attentive and accurate eye in every part and point of the human body, by the congeniality and harmony of the various parts. Is there any occasion to prove that the power of thinking resides not in the foot, nor in the hand, nor in the back, but in the head and its internal parts?
The moral life of man particularly reveals itself in the lines, marks, and transitions of the countenance. His moral powers and desires, his irritability, sympathy, and antipathy, his facility of attracting or repelling the objects that surround him—these are all summed up in, and painted upon, his countenance when at rest.
Not only do mental and moral traits evince themselves in the physiognomy, but also health and sickness; and I believe that by repeatedly examining the firm parts and outlines of the bodies and countenances of the sick, disease might be diagnosed, and even that liability to disease might be predicted in particular cases.
The same vital powers that make the heart beat and the fingers move, roof the skull and arch the finger-nails. From the head to the back, from the shoulder to the arm, from the arm to the hand, from the hand to the finger, each depends on the other, and all on a determinate effect of a determinate power. Through all nature each determinate power is productive of only such and such determinate effects. The finger of one body is not adapted to the hand of another body. The blood in the extremity of the finger has the character of the blood in the heart. The same congeniality is found in the nerves and in the bones. One spirit lives in all. Each member of the body, too, is in proportion to the whole of which it is a part. As from the length of the smallest member, the smallest joint of the finger, the proportion of the whole, the length and breadth of the body may be found; so also may the form of the whole be found from the form of each single part. When the head is long, all is long; when the head is round, all is round; when the head is square, all is square.
One form, one mind, one root appertain to all. Each organised body is so much a whole that, without discord, destruction, or deformity, nothing can be added or subtracted. Those, therefore, who maintain that conclusion cannot be drawn from a part to the whole labour under error, failing to comprehend the harmony of nature.
II.—Physiognomy and the Features
The Forehead. The form, height, arching, proportion, obliquity, and position of the skull, or bone of the forehead, show the propensity of thought, power of thought, and sensibility of man. The position, colour, wrinkles, tension of the skin of the forehead, show the passions and present state of the mind. The bones indicate the power, the skin the application of power.
I consider the outline and position of the forehead to be the most important feature in physiognomy. We may divide foreheads into three principal classes—the retreating, the perpendicular, and the projecting, and each of these classes has a multitude of variations.
A few facts with respect to foreheads may now be given.
The higher the forehead, the more comprehension and the less activity.
The more compressed, short, and firm the forehead, the more compression and firmness, and the less volatility in the man.
The more curved and cornerless the outline, the more tender and flexible the character; and the more rectilinear, the more pertinacious and severe the character.
Perfect perpendicularity implies lack of understanding, but gently arched at top, capacity for cold, tranquil, profound thought.
A projecting forehead indicates imbecility, immaturity, weakness, stupidity.
A retreating forehead, in general, denotes superior imagination, wit, acuteness.
A forehead round and prominent above, straight below, and, on the whole, perpendicular, shows much understanding, life, sensibility, ardour.
An oblique, rectilinear forehead is ardent and vigorous.
Arched foreheads appear properly to be feminine.
A forehead neither too perpendicular nor too retreating, but a happy mean, indicates the post-perfect character of wisdom.
I might also state it as an axiom that straight lines considered as such, and curves considered as such, are related as power and weakness, obstinacy and flexibility, understanding and sensation.
I have seen no man with sharp, projecting eyebones who was not inclined to vigorous thinking and wise planning.
Yet, even lacking sharpness, a head may be excellent if the forehead sink like a perpendicular wall upon horizontal eyebrows, and be greatly rounded towards the temples.
Perpendicular foreheads, projecting so as not to rest immediately upon the nose, and small, wrinkled, short, and shining, indicate little imagination, little understanding, little sensation.
Foreheads with many angular, knotty protuberances denote perseverance and much vigorous, firm, harsh, oppressive, ardent activity.
It is a sure sign of a clear, sound understanding and a good temperament when the profile of the forehead has two proportionate arches, the lower of which projects.
Eyebones with well-marked, firm arches I never saw but in noble and great men.
Square foreheads with extensive temples and firm eyebones show circumspection and steadiness of character.
Perpendicular wrinkles, if natural, denote application and power. Horizontal wrinkles and those broken in the middle or at the extremities generally denote negligence or want of power.
Perpendicular, deep indentings in the forehead between the eyebrows, I never met save in men of sound understanding and free and noble minds, unless there were some positively contradictory feature.
A blue frontal vein, in the form of a Y, when in an open, smooth, well-arched forehead, I have only found in men of extraordinary talents and of ardent and generous character.
The following are the traits of a perfectly beautiful, intelligent, and noble forehead.
In length it must equal the nose, or the under part of the face. In breadth it must be either oval at the top-like the foreheads of most of the great men of England—or nearly square. It must be free from unevenness and wrinkles, yet be able to wrinkle when deep in thought, afflicted by pain, or moved by indignation. It must retreat above and project beneath. The eyebones must be simple, horizontal, and, if seen from above, must present a simple curve. There should be a small cavity in the centre, from above to below, and traversing the forehead so as to separate it into four divisions perceptible in a clear descending light. The skin must be more clear on the forehead than in other parts of the countenance.
Foreheads short, wrinkled, and knotty, are incapable of durable friendship.
Be not discouraged though a friend, an enemy, a child, or a brother transgress, for so long as he have a good, well-proportioned, open forehead there is still hope of improvement.
THE EYES AND EYEBROWS. Blue eyes are generally more indicative of weakness and effeminacy than brown or black. Certainly there are many powerful men with blue eyes, but I find more strength, manhood, thought with brown.
Choleric men have eyes of every colour, but rather brown or greenish than blue. A propensity to green is an almost decisive token of ardour, fire, and courage.
Wide open eyes, with the white visible, I have often observed both in the timid and phlegmatic, and in the courageous and rash.
Meeting eyebrows were supposed to be the mark of craft, but I do not believe them to have this significance. Angular, strong, interrupted eyebrows denote fire and productive activity. The nearer the eyebrows to the eyes, the more earnest, deep, and firm the character. Eyebrows remote from each other denote warm, open, quick sensations. White eyebrows signify weakness; and dark brown, firmness. The motion of the eyebrows contains numerous expressions, especially of ignoble passions.
THE NOSE. I have generally considered the nose the foundation or abutment of the brain, for upon this the whole power of the arch of the forehead rests. A beautiful nose will never be found accompanying an ugly countenance. An ugly person may have fine eyes, but not a handsome nose.
I have never seen a nose with a broad back, whether arched or rectilinear, that did not belong to an extraordinary man. Such a nose was possessed by Swift, Caesar Borgia, Titian, etc. Small nostrils are usually an indubitable sign of unenterprising timidity. The open, breathing nostril is as certain a token of sensibility.
THE MOUTH AND LIPS. The contents of the mind are communicated to the mouth. How full of character is the mouth! As are the lips, so is the character. Firm lips, firm character; weak lips, weak character. Well-defined, large, and proportionate lips, the middle line of which is equally serpentine on both sides, and easy to be drawn, are never seen in a bad, mean, common, false, vicious countenance. A lipless mouth, resembling a single line, denotes coldness, industry, a love of order, precision, house-wifery, and, if it be drawn upwards at the two ends, affectation, pretension, vanity, malice. Very fleshy lips have always to contend with sensuality and indolence. Calm lips, well closed, without constraint, and well delineated, certainly betoken consideration, discretion, and firmness. Openness of mouth speaks complaint, and closeness, endurance.
THE CHIN. From numerous experiments, I am convinced that the projecting chin ever denotes something positive, and the retreating something negative. The presence or absence of strength in man is often signified by the chin.
I have never seen sharp indentings in the middle of the chin save in men of cool understanding, unless when something evidently contradictory appeared in the countenance. The soft, fat, double chin generally points out the epicure; and the angular chin is seldom found save in discreet, well-disposed, firm men. Flatness of chin speaks the cold and dry; smallness, fear; and roundness, with a dimple, benevolence.
SKULLS. HOW much may the anatomist see in the mere skull of man! How much more the physiognomist! And how much more still the anatomist who is a physiognomist! If shown the bald head of Caesar, as painted by Rubens or Titian or Michael Angelo, what man would fail to notice the rocky capacity which characterises it, and to realise that more ardour and energy must be expected than from a smooth, round, flat head? How characteristic is the skull of Charles XII.! How different from the skull of his biographer Voltaire! Compare the skull of Judas with the skull of Christ, after Holbein, and I doubt whether anyone would fail to guess which is the skull of the wicked betrayer and which the skull of the innocent betrayed. And who is unacquainted with the statement in Herodotus that it was possible on the field of battle to distinguish the skulls of the effeminate Medes from the skulls of the manly Persians? Each nation, indeed, has its own characteristic skull.
III.—Nation, Sex, and Family
NATIONAL PHYSIOGNOMY. It is undeniable that there is a national physiognomy as well as national character. Compare a negro and an Englishman, a native of Lapland and an Italian, a Frenchman and an inhabitant of Tierra del Fuego. Examine their forms, countenances, characters, and minds. This difference will be easily seen, though it will sometimes be very difficult to describe it scientifically.
The following infinitely little is what I have hitherto observed in the foreigners with whom I have conversed.
I am least able to characterise the French, They have no traits so bold as the English, nor so minute as the Germans. I know them chiefly by their teeth and their laugh. The Italians I discover by the nose, small eyes, and projecting chin. The English by their foreheads and eyebrows. The Dutch by the rotundity of their heads and the weakness of the hair. The Germans by the angles and wrinkles round the eyes and in the cheeks. The Russians by the snub nose and their light-coloured or black hair.
I shall now say a word concerning Englishmen in particular. Englishmen have the shortest and best-arched foreheads—that is to say, they are arched only upwards, and, towards the eyebrows, either gently recline or are rectilinear. They seldom have pointed, usually round, full noses. Their lips are usually large, well defined, beautifully curved. Their chins are round and full. The outline of their faces is in general large, and they never have those numerous angles and wrinkles by which the Germans are so especially distinguished. Their complexion is fairer than that of the Germans.
All Englishwomen whom I have known personally, or by portrait, appear to be composed of marrow and nerve. They are inclined to be tall, slender, soft, and as distant from all that is harsh, rigorous, or stubborn as heaven is from earth.
The Swiss have generally no common physiognomy or national character, the aspect of fidelity excepted. They are as different from each other as nations the most remote.
THE PHYSIOGNOMICAL RELATION OF THE SEXES. Generally speaking, how much more pure, tender, delicate, irritable, affectionate, flexible, and patient is woman than man. The primary matter of which woman is constituted appears to account for this difference. All her organs are tender, yielding, easily wounded, sensible, and receptive; they are made for maternity and affection. Among a thousand women, there is hardly one without these feminine characteristics.
This tenderness and sensibility, the light texture of their fibres and organs, render them easy to tempt and to subdue, and yet their charms are more potent than the strength of man. Truly sensible of purity, beauty and symmetry, woman does not always take time to reflect on spiritual life, spiritual death, spiritual corruption.
The woman does not think profoundly; profound thought is the prerogative of the man; but women feel more. They rule with tender looks, tears, and sighs, but not with passion and threats, unless they are monstrosities. They are capable of the sweetest sensibility, the deepest emotion, the utmost humility, and ardent enthusiasm. In their faces are signs of sanctity which every man honours.
Owing to their extreme sensibility and their incapacity for accurate inquiry and firm decision, they may easily become fanatics.
The love of women, strong as it is, is very changeable; but their hatred is almost incurable, and is only to be overcome by persistent and artful flattery. Men usually see things as a whole, whereas women take more interest in details.
Women have less physical courage than men. Man hears the bursting thunders, views the destructive bolt with serene aspect, and stands erect amid the fearful majesty of the torrent. But woman trembles at the lightning and thunder, and seeks refuge in the arms of man.
Woman is formed for pity and religion; and a woman without religion is monstrous; and a woman who is a freethinker is more disgusting than a woman with a beard.
Woman is not a foundation on which to build. She is the gold, silver, precious stones, wood, hay, stubble—the materials for building on the male foundation. She is the leaven, or, more expressly, she is oil to the vinegar of man. Man singly is but half a man, only half human—a king without a kingdom. Woman must rest upon the man, and man can be what he ought to be only in conjunction with the woman.
Some of the principal physiognomical contrasts may be summarised here.
Man is the most firm; woman the most flexible.
Man is the straightest; woman the most bending.
Man stands steadfast; woman gently retreats.
Man surveys and observes; woman glances and feels.
Man is serious; woman is gay.
Man is the tallest and broadest; woman the smallest and weakest.
Man is rough and hard; woman is smooth and soft.
Man is brown; woman is fair.
The hair of the man is strong and short; the hair of woman is pliant and long.
Man has most straight lines; woman most curved.
The countenance of man, taken in profile, is not so often perpendicular as that of woman.
FAMILY PHYSIOGNOMY. The resemblance between parents and children is very commonly remarkable. Family physiognomical resemblance is as undeniable as national physiognomical resemblance. To doubt this is to doubt what is self-evident.
When children, as they increase in years, visibly increase in their physical resemblance to their parents, we cannot doubt that resemblance in character also increases. Howsoever much the character of children may seem to differ from that of their parents, yet this difference will be found to be due to great difference in external circumstances.
JUSTUS VON LIEBIG
Baron Freiherr Justus von Liebig, one of the most illustrious chemists of his age, was born on May 12, 1803, at Darmstadt, Germany, the son of a drysalter. It was in his father's business that his interest in chemistry first awoke, and at fifteen he became an apothecary's assistant. Subsequently, he went to Erlangen, where he took his doctorate in 1822; and afterwards, in Paris, was admitted to the laboratory of Gay-Lussac as a private pupil. In 1824 he was appointed a teacher of chemistry in the University of Giessen in his native state. Here he lived for twenty-eight years a quiet life of incessant industry, while his fame spread throughout Europe. In 1845 he was raised to the hereditary rank of baron, and seven years later was appointed by the Bavarian government to the professorship of chemistry in the University of Munich. Here he died on April 18, 1873. The treatise on "Animal Chemistry, or Organic Chemistry in its Relations to Physiology and Pathology," published in 1842, sums up the results of Liebig's investigations into the immediate products of animal life. He was the first to demonstrate that the only source of animal heat is that produced by the oxidation of the tissues.