Part 3

We pass to the next chapter in the history, which professes to explain the gradual formation of a solar system by a process of cooling and shrinking, to which the central orb is exposed. And here we are met by a difficulty at the outset; for the existence of comets with their very eccentric orbits is wholly irreconcilable with the theory. At their perihelion, many of these bodies pass within the orbit of Mercury, while the aphelion of some lies without the path of Uranus. Where were they, when the body of the sun filled up the whole of the vast sphere circumscribed by the orbit of the remotest planet? If we suppose that they are late comers, after the rest of our system was perfected,--that they were generated by themselves in distant regions of space, and, having strayed about, orphan-like, for a while, they accidentally crossed our track, and were taken as adopted children into our family, another question remains to be answered. Why did they not remain in their first position, absorb their full share of nebulous matter, beget a respectable family of planets, and take rank as chiefs of their own clan? These comparatively anomalous bodies are great stumbling-blocks for the _soi-disant_ historians of creation.

Again, if an immense orb be formed, the parts of which cohere strongly enough for the whole to turn upon its axis as one body, the process of cooling can go on only from the surface. A crust may finally be formed there; but we see not how the refrigeration and shrinking of the interior parts can then go on separately, until the mass in the centre finally becomes detached from its envelope, like a shrivelled nut from its shell. Our earth is cooling down at this moment, unless the warmth which it receives from the sun exactly counterbalances the loss by radiation of internal heat. But the exterior and interior do not cool by different radiations, nor is there, so far as we know, the least tendency in the central mass to shrink separately, so as to detach itself from the surrounding crust. As deep as we can penetrate towards the centre, we find the heat regularly increase,--just as we might expect, if the only absolute loss of heat be from the surface.

If the matter now concentrated in the sun, and that which forms the several planets with their secondaries, were all moulded into one mass, and then dilated so as to fill the vast sphere of which the orbit of Uranus forms a circumference, the substance would evidently be in a state of extreme tenuity and diffusion. Immense as the mass of the sun now is, it is but a mere nut at the centre of the grand globe which we are now considering. Expanded to such vast dimensions, we cannot conceive of it as a solid spheroid turning upon its axis, but only as a mass of fluid or vapor, in which a circular motion would generate only vortices or whirlwinds. In such an aggregation of subtile matter, no crust could be solidified on the outer ring, and then detached from the mass within; indeed, any separation of the parts under such circumstances is inconceivable. Even a rotary motion could not be established in it, except by an impulse received from without; for there is every reason to believe, that the movement of a homogeneous fluid towards its centre, if it could take place without disturbing causes, would be in radial lines, and not in a spiral.

Our author brings into view all the mathematical proportions and uniform relations which exist between the constituent bodies of the solar system, in order to indicate the probability of their formation from the constant working of one material cause. Thus he remarks, that the primary planets all move nearly in one plane, and "show a progressive increase of bulk and diminution of density, from the one nearest to the sun to that which is most distant." But he passes over other characteristics of these bodies, equally important, which are quite irregular, and cannot be traced to the operation of one law. Compare the periods of rotation on their respective axes, and we find no correspondence, no indication that the revolving motion was imparted to all by one inflexible law. The first four planets, counting from the sun, perform their rotation in nearly the same time, namely, twenty-four hours. But Jupiter's period is a little less, and Saturn's a little more, than ten hours. Again, Jupiter's axis of rotation is nearly perpendicular to the plane of the ecliptic, while that of Mars is inclined at an angle of fifty-nine degrees forty-two minutes. Another irregularity, still more fatal to the theory, is found in the number of satellites by which the respective planets are attended. Saturn has seven, beside the two rings; Jupiter has four, Mars has none, and the earth has but one. On the single hypothesis, that our system was formed by rings successively thrown off from a central body by a process of refrigeration and contraction, these irregularities are inexplicable. Mars, it seems, did not shrink at all, while Jupiter cast off four separate rings, and the earth produced its single moon. The distances of these bodies from their primaries are also quite irregular; in the case of Jupiter, the outermost of the satellites revolves at a distance which is only twenty-seven times the radius of the primary, and the innermost is distant but six times that radius. This planet, consequently, has shrunk to one twenty-seventh part of its original diameter, and in so doing, has formed four moons; the earth has shrunk to one sixtieth part of its first diameter, and still has produced but one satellite. If the same law had prevailed in the two cases, we ought to have nine or ten moons.

We need not analyze with any great minuteness the geological facts and hypotheses incorporated into this magnificent history of creation. As will be seen hereafter, the violent and sweeping transformations and convulsions that the earth's crust has undergone directly conflict with our author's theory, and afford the strongest presumption, that an extraneous cause has frequently interfered, at different periods, to repair the desolation produced by the unassisted working of natural laws, to bring order out of chaos, and to people the desert earth anew with animated tribes. The only general fact of much moment, which our author has drawn from the discoveries of geologists, for the confirmation of his own hypothesis, is, according to his own account, one of the most questionable doctrines in the whole science,--one of a negative character, on which we can never rely with full assurance, till the researches of man have probed every fold, and examined every thread in the texture, of the earth's garment, and thus shown that no evidence can possibly be discovered to the contrary. The alleged fact is that, in the early formations of rock--the first pages in the history of the earth's surface--are found the remains of animals and vegetables only of the lowest type and most imperfect development; while, in the later strata, forms more and more advanced are discovered; so that there seems to have been a constant progress along the line leading to the higher forms of organization. The testimony which goes to support this assertion is wholly negative. The geologist reasons thus: The more perfect organisms have not been discovered in the earlier strata; _therefore_, they do not exist in them. When, in a different connection, it suits our author's purpose to throw doubt on the very postulate which is here admitted, he holds the following language.

"These, it must be owned, are less strong traces of the birds than we possess of the reptiles and other tribes; but it must be remembered, that the evidence of fossils, as to the absence of any class of animals from a certain period of the earth's history, can never be considered as more than negative. Animals, of which we find no remains in a particular formation, may, nevertheless, have lived at the time, and it may have only been from unfavorable circumstances that their remains have not been preserved for our inspection. The single circumstance of their being little liable to be carried down into seas might be the cause of their non-appearance in our quarries."--p. 95.

In truth, the researches of geologists are every day bringing to light new facts, which compel them to modify or abandon many of the positions they formerly held; so that a considerable portion of the science is a mere quicksand of shifting theories. We need only allude to the various suppositions respecting the origin of drift, and to the numerous modifications of the glacial theory. Important discoveries have been made within a short time, showing that certain animal tribes had their origin much farther back than was at first supposed. A few years ago, reptiles were believed to be the highest type of life that existed during the era of the new red sand-stone. But Professor Hitchcock's recent discovery in this stone of the footprints of gigantic birds has added a higher class to the zooelogy of the period; and within a few months, in the same red sand-stone of the Connecticut valley, tracks of two or three species of quadrupeds have been found, some of them being probably mammifers of a lower grade. It is true, no fossil remains of these animals have been brought to light; but this want only renders the discovery more significant for our present purpose. It shows that certain animals must have lived at the period in question, though their remains have not yet been found; and from the greater age of the rocks then formed, and the consequent greater number of convulsions of the earth's surface to which they have been subjected, these remains may have entirely disappeared. It is a curious fact, also, that the animal remains of that period, which have come down to us, belong to genera so constituted, that their bodies might well survive, if we may so speak, the shocks which would have destroyed every trace of some more delicate, or more finely organized, beings. We find remains of the flint-shielded animalcules, the hard-shelled mollusca, and the cartilaginous fishes; but the bodies of mammalia, birds, and even the higher species of fishes, some of which we may suppose to have been more tender and corruptible, have utterly perished. Here and there, an individual of their number left the print of its foot on the sand, which subsequently hardened into rock, and brought down to our times a faint vestige of its past existence.

We are not attempting to impugn the credit of geological science in general, which would be a wholly futile task. The multitude of facts respecting the present constitution of the earth's crust, recently made known by laborers in this department, are among the most curious and most pregnant discoveries of modern times. But when we come to the formation of theories respecting the past history of the earth, in order to account for the phenomena at present visible on its surface, we are evidently afloat on a sea of conjecture, each hypothesis being valid only till a more plausible one is proposed,--which happens very frequently,--or till it is effectually disproved by some new discovery in the rocky strata. A fertile imagination and a bold face are among the most striking traits of our more daring geologists. Grant to one of this character a few modest postulates,--give him certain millions of years, a sufficient number of earthquakes, a whole battery of volcanoes, a few ocean deluges, and the rise and fall of half a dozen continents,--and he will frame a theory off-hand, which will account for the most perplexing phenomena. Our author is certainly entitled to take his place at the very head of this class of speculatists.

In accounting for the work of creation by the natural and unassisted development of the inherent qualities of brute matter, the great difficulty is found at the first link in the chain of animated being. How can we explain the commencement of _life_? We must have a clear idea of the whole scope of this problem, before we can make any attempt at its solution. Life, then, is _not_ mere organization, though most materialists, philosophers, like our author, willingly confound the two things; to hear them reason, one would almost suppose that there was no difference between a dead man and a living one. Organization is subservient to life, ministers to it, manifests it,--supports it, if you please,--but does not constitute it. He must be a bolder man than we are, who will undertake to say _what it is_; but we can very safely declare _what it is not_; and in any particular form or aggregation of matter, whether organic or inorganic, we can give a shrewd guess as to its presence or absence. It may be said, that we beg the question by assuming that organization is not life; it may be so; but it is quite too much to allow the materialist quietly to take the opposite doctrine for granted. He must know the full extent of his task,--that it is necessary for him not only to construct the machine, but actually to set it in motion, so that it shall afterwards run on of its own accord. It is very easy to frame a partial definition of life, by merely describing one or two of its characteristic functions; and then, because some action can be detected between the particles of brute matter, which resembles the exercise of these functions, boldly to declare that the whole mystery is solved. Thus it is said, that life is nothing but the accretion of similar substances, or the addition of like unto like; and as this occurs in crystallization, which is confessedly a phenomenon of inorganic matter, therefore there is no fundamental difference between the properties of living and dead substances. We deny the first proposition; nutrition is not the only characteristic of life, and the nutritive process, whether in vegetables or animals, is not mere accretion, but assimilation. It has been said, though the assertion is by no means fully proved, that assimilation is only a finer kind of chemistry, the constituent principles being brought together only by their natural affinities. Even if this were true, if the stomach and the digestive apparatus were only a well furnished chemical laboratory, fit for conducting the most delicate experiments, the great difficulty would still remain. The question might yet be asked, Where is the chemist? And this is the fundamental question, which the materialists never attempt to answer, but quietly evade.

The difference between an inorganic and an organic body has been explained by Coleridge clearly enough for our purpose. In the former,--a sheaf of corn, for instance,--the whole is nothing more than a collection of the individual parts; in the latter,--an animal,--the whole is the effect of, or results from, the parts. In the latter case, the whole is every thing, and the parts are comparatively nothing. One of the great effects of life is to keep the parts in subjection to the whole, making them contribute to its support and growth, and thus maintaining the unity of the system. The stomach digests, the lungs inhale air, the heart beats, and the blood circulates; and as the joint effect, or as the common supporter,--it matters not which,--of these operations, _life_ continues, and the animated being is a unit; it has not merely virtual, but essential unity. The reciprocal action of the respiratory, circulating, and nervous systems is absolutely necessary to life. The animal dies, and this unity, this subservience of the parts to the whole, immediately ceases. In the functions of the living body, it may be that the ordinary laws of chemistry are preserved, and that the elements of carbon, oxygen, and hydrogen combine and separate according to their ordinary affinities, and in no unusual proportions. But after death, at any rate, quite a different set of chemical laws come into play, and produce a result which is the very opposite of that before effected. There is no longer any unanimity or cooeperation; instead of sustaining or building up the animal tissues, the affinities now in operation tear down, destroy, and resolve them into their ultimate elements,--each part following out its own law of destruction or resolution, irrespectively of the others.

"There is in living organic matter a principle constantly in action, the operations of which are in accordance with a rational plan, so that the individual parts which it creates in the body are adapted to the design of the whole; and this it is which distinguishes organism. Kant says, 'The cause of the particular mode of existence of each part of a living body resides in the whole, while in dead masses each part contains this cause within itself.' This explains why a mere part separated from an organized whole generally does not continue to live; why, in fact, an organized body appears to be one and indivisible. And since the different parts of an organized body are heterogeneous members of one whole, and essential to its perfect state, the trunk cannot live after the loss of one of these parts."--_Mueller's Physiology_, Vol. I., p. 19.

The apparent exceptions to this statement--as in the case of the polypes, which multiply by fissiparous generation, or by spontaneous division of their bodies into parts, each part becoming a perfect animal--are only apparent. These creatures, which are low down in the scale of being, exemplify what Mr. Owen calls "the law of vegetative or irrelative repetition," as they have many organs performing the same function, and not related to each other by combination for the performance of a higher function. Thus, a Polygastrian has many assimilative sacs, each performing the office of a stomach irrespective of the rest. In the insect tribe, the respiratory function, instead of being performed by one set of lungs for the whole body, is carried on through a series of minute and highly ramified tubes, which traverse every part of the body, and open to the air by a great number of orifices. In some instances, both respiration and digestion seem to take place over the whole surface of the body; for Trembley found at least one case, in which the animal digested its food equally well, after it had been turned inside out. A number of similar parts being repeated in each segment of the individual, the body can be divided, and the several portions, each still containing some of all the organs essential to the whole, will continue to live separately. The severed parts will even continue to grow, and to develope other organs convenient for individual existence. But most animals, especially the more perfect, do not constitute an aggregate of similar parts united by one trunk, and therefore propagation by division is in them impossible. The ovum, when separated from the parent, is an entire animal only _potentially_; during its development, the essential parts which constitute the _actual_ whole are produced. In the case of the polyps, we have only to suppose that the ovum remains connected with the parent being, till all, or nearly all, its essential parts are produced. It is then shed not as a mere ovum, but as an animal nearly or wholly complete.

Now, all the instances adduced by our author, to show similarity of action in the organic and the inorganic world, are irrelevant. The analogies are not merely imperfect; they are no analogies at all. Crystals increase by the aggregation of new particles on the external surfaces of the parts already formed; there is no consentaneous operation of the parts on the whole. The molecules of crystals are homogeneous throughout, and the several aggregates of these molecules are independent of each other; while organized bodies are composed of parts perfectly dissimilar from each other, but all of which conspire to one end. "The growth of organized bodies," says Mueller, "takes place in all particles of their substance at the same time, while the increase of the mass in inorganic bodies is produced by external apposition." Frostwork on the windows may resemble vegetable _forms_; but it has no resemblance whatever to vegetable _life_. Electricity may counterfeit the _action of life_, for a moment, on a particular limb, by causing the muscles to twitch; but it does not counterfeit _life itself_, by causing all the parts again to contribute to the sustentation of the whole. A French chemist, by electric action, may have produced _globules_ in albumen; there is nothing very wonderful in that; any one may blow bubbles in a viscid fluid. The resemblance between these globules and proper germinal vesicles amounts to nothing more than similarity of outward shape; there is no more real resemblance between them than between the oval lump of chalk which farmers sometimes put into a hen's nest, in order to deceive poor Dame Partlet, and the real egg which the hen deposits by the side of it. Certainly, the imponderable agents, heat, light, and electricity, are in some mysterious way _connected with_ life, so as to contribute to its support; there is nothing more in this assertion than in the familiar proposition, that a seed will germinate only under the proper conditions of soil and climate; but that these agents, acting on inorganic matter, ever _create_ or _commence_ life is a pure hypothesis, not supported even by the shadow of a fact.

Having thus shown how weak are the general considerations in favor of the theory, that animated beings may be created out of inorganic matter by mere natural laws, we should proceed to consider the direct evidence adduced to prove that life has actually been produced in this way. Here the whole question is opened respecting the alleged instances of equivocal generation, and we have neither space nor ability to discuss them at length. Those who are curious respecting the question may find a brief summary of the evidence on both sides in a former number of this Journal.[1] We can mention only a few facts and arguments, which show the extreme improbability of the doctrine supported by our author and a few other theorists.