What now of the unities of form and power in protoplasm? By form, Mr. Huxley will be found to mean the general appearance and structure; and by faculty or power, the action exhibited. Now it will be very easy to prove that, in neither respect, do all specimens of protoplasm agree. Mr. Huxley’s representative protoplasm, it appears, is that of the nettle-sting; and he describes it as a granulated, semi-fluid body, contractile in mass, and contractile also in detail to the development of a species of circulation. Stricker, again, speaks of it as a homogeneous substance, in which any granules that may appear must be considered of foreign importation, and in which there are no evidences of circulation. In this last respect, then, that Mr. Huxley should talk of “tiny Maelstroms,” such as even in the silence of a tropical noon might stun us, if heard, as “with the roar of a great city,” may be viewed, perhaps, as a rise into poetry beyond the occasion.
Further, according to Stricker, protoplasm varies almost infinitely in consistence, in shape, in structure, and in function. In consistence, it is sometimes so fluid as to be capable of forming in drops; sometimes semi-fluid and gelatinous; sometimes of considerable resistance. In shape—for to Stricker the cells are now protoplasm—we have club-shaped protoplasm, globe-shaped protoplasm, cup-shaped protoplasm, bottle-shaped protoplasm, spindle-shaped protoplasm—branched, threaded, ciliated protoplasm,—circle-headed protoplasm—flat, conical, cylindrical, longitudinal, prismatic, polyhedral, and palisade-like protoplasm. In structure, again, it is sometimes uniform and sometimes reticulated into interspaces that contain fluid. In function, lastly—and here we have entered on the consideration of faculty or power—some protoplasm is vagrant (so to translate wandernd), and of unknown use, like the colorless blood-corpuscles.
In reference to these, as strengthening the argument, and throwing much light generally, I break off a moment to say that, very interesting as they are in themselves, and as Recklinghausen, in especial, has made them, Mr. Huxley’s theory of them disagrees considerably with the prevalent German one. He speaks of them as the source of the body in general, yet, in his Physiology, he talks of the spleen, the lymphatics, and even the liver—parts of the body—as their source. They are so few in number that, while Mr. Huxley is thankful to be able to point to the inside of the lips as a seat for them, they bear to the red corpuscles only the proportion of 1 to 450. This disproportion, however, is no bar to Mr. Huxley’s derivation of the latter from the former. But the fact is questioned. The Germans, generally, for their, part, describe the colorless, or vagrant, blood-corpuscles as probably media of conjugation or reparation, but acknowledge their function to be as yet quite unknown; while Rindfleisch, characterizing the spleen as the grave of the red, and the womb of the white, corpuscles, evidently refers the latter to the former. This, indeed, is a matter of direct assertion with Preyer, who has “shown that pieces of red blood-corpuscles may be eaten by the amoeboid cells of the frog,” and holds that the latter (the white corpuscles) proceed directly from the former (the red corpuscles); so that it seems to be determined in the mean time that there is no proof of the reverse being the fact.
In function, then, to resume, some protoplasm is vagrant, and of unknown use. Some again produces pepsine, and some fat. Some at least contains pigment. Then there is nerve-protoplasm, brain-protoplasm, bone-protoplasm, muscle-protoplasm, and protoplasm of all the other tissues, no one of which but produces only its own kind, and is uninterchangeable with the rest. Lastly, on this head, we have to point to the overwhelming fact that there is the infinitely different protoplasm of the various infinitely different plants and animals, in each of which its own protoplasm, as in the case of that of the various tissues, but produces its own kind, and is uninterchangeable with that of the rest.
It may be objected, indeed, that these latter are examples of modified protoplasm. The objection of modification, as said, we have to see by itself later; but, in the mean time, it may be asked, Where are we to begin, not to have modified protoplasm? We have the example of Mr. Huxley himself, who, in the nettle-sting, begins already with modified protoplasm; and we have the authority of Rindfleisch for asserting that “in every different tissue we must look for a different initial term of the productive series.” This, evidently, is a very strong light on the original multiplicity of protoplasm, which the consideration, as we have seen, of the various plants and animals, has made, further, infinite. This is enough; but there is no wish to evade beginning with the very beginning—with absolutely pure initial protoplasm, if it can but be given us in any reference. The simple egg—that, probably is the beginning—that, probably, is the original identity; yet even there we find already distribution of the identity into infinite difference. This, certainly, with reference to the various organisms, but with reference also to the various tissues. That we regard the egg as the beginning, and that we do not start, like the smaller exceptional physiological school, with molecules themselves, depends on this, that the great Germans so often alluded to, Kühne among them, still trust in the experiments of Pasteur; and while they do not deny the possibility, or even the fact, of molecular generation, still feel justified in denying the existence of any observation that yet unassailably attests a generatio æquivoca. By such authority as this the simple philosophical spectator has no choice but to take his stand; and therefore it is that I assume the egg as the established beginning, so far, of all vegetable and animal organisms. To the egg, too, as the beginning, Mr. Huxley, though the lining of the nettle-sting is his representative protoplasm, at least refers. “In the earliest condition of the human organism,” he says, in allusion to the white (vagrant) corpuscles of the blood, “in that state in which it has but just become distinguished from the egg in which it arises, it is nothing but an aggregation of such corpuscles, and every organ of the body was once no more than such an aggregation.” Now, in beginning with the egg—an absolute beginning being denied us in consequence of the pre-existent infinite difference of the egg or eggs themselves—we may gather from the German physiologists some such account of the actual facts as this.
The first change signalized in the impregnated egg seems that of Furchung, or furrowing—what the Germans call the Furchungskugeln, the Dotterkugeln, form. Then these Kugeln—clumps, eminences, monticles, we may translate the word—break into cells; and these are the cells of the embryo. Mr. Huxley, as quoted, refers to the whole body, and every organ of the body, as at first but an aggregation of colorless blood-corpuscles; but in the very statement which would render the identity alone explicit, the difference is quite as plainly implicit. As much as this lies in the word “organs,” to say nothing of “human.” The cells of the “organs,” to which he refers, are even then uninterchangeable, and produce but themselves. The Germans tell us of the Keimblatt, the germ-leaf, in which all these organs originate. This Blatt, or leaf, is threefold, it seems; but even these folds are not indifferent. The various cells have their distinct places in them from the first. While what in this connection are called the epithelial and endorthelial tissues spring respectively from the upper and under leaf, connective tissues, with muscle and blood, spring from the middle one. Surely in such facts we have a perfect warrant to assert the initial non-identity of protoplasm, and to insist on this, that, from the very earliest moment—even literally ab ovo—brain-cells only generate brain-cells, bone-cells bone-cells, and so on.
These considerations on function all concern faculty or power; but we have to notice now that the characteristic and fundamental form of power is to Mr. Huxley contractility. He even quotes Goethe in proof of contractility being the main power or faculty of Man! Nevertheless it is to be said at once that, while there are differences in what protoplasm is contractile, all protoplasm is not contractile, nor dependent on contractility for its functions. In the former respect, for example, muscle, while it is the contractile tissue special, is also to Mr. Huxley protoplasm; yet Stricker asserts the inner construction of the contractile substance, of which muscle-fibre virtually consists, to be essentially different from contractile protoplasm. Here, then, we have the contractile substance proper “essentially different” from the contractile source proper. In the latter respect, again, we shall not call in the uncontractible substances which Mr. Huxley himself denominates protoplasm—bread, namely, roast mutton, and boiled lobster; but we may ask where—even in the case of a living body—is the contractility of white of egg? In this reference, too, we may remark that Kühne, who divides the protoplasm of the epidermis into three classes, has been unable to distinguish contractility in his own third class. Lastly, where, in relation to the protoplasm of the nervous system, is there evidence of its contractility? Has any one pretended that thought is but the contraction of the brain; or is it by contraction that the very nerves operate contraction—the nerves that supply muscles, namely? Mr. Huxley himself, in his Physiology, describes nervous action very differently. There conduction is spoken of without a hint of contraction. Of the higher faculties of man I have to speak again; but let us just ask where, in the case of any pure sensation—smell, taste, touch, sound, color—is there proof of any contraction? Are we to suppose that between the physical cause of heat without and the mental sensation of heat within, contraction is anywhere interpolated? Generally, in conclusion here, while reminding of Virchow’s testimony to the inherent inequalities of cell-capacity, let us but, on the question of faculty, contrast the kidney and the brain, even as these organs are viewed by Mr. Huxley. To him the one is but a sieve for the extrusion of refuse: the other thinks Newton’s ‘Principia’ and Iliads of Homer.
Probably, then, in regard to any continuity in protoplasm of power, of form, or of substance, we have seen lacunæ enow. Nay, Mr. Huxley himself can be adduced in evidence on the same side. Not rarely do we find in his essay admissions of probability where it is certainty that is alone in place. He says, for example, “It is more than probable that when the vegetable world is thoroughly explored we shall find all plants in possession of the same powers.” When a conclusion is decidedly announced, it is rather disappointing to be told, as here, that the premises are still to collect. “So far,” he says again, “as the conditions of the manifestations of the phenomena of contractility have yet been studied.” Now, such a so far need not be very far; and we may confess in passing, that from Mr. Huxley the phrase, “the conditions of the manifestations of the phenomena” grates. We hear again that it is “the rule rather than the exception,” or that “weighty authorities have suggested” that such and such things “probably occur,” or, while contemplating the nettle-sting, that such “possible complexity” in other cases “dawns upon one.” On other occasions he expresses himself to the effect that “perhaps it would not yet be safe to say that all forms,” etc. Nay, not only does he directly say that “it is by no means his intention to suggest that there is no difference between the lowest plant and the highest, or between plants and animals,” but he directly proves what he says, for he demonstrates in plants and animals an essential difference of power. Plants can assimilate inorganic matters, animals can not, etc. Again, here is a passage in which he is seen to cut his own “basis” from beneath his own feet. After telling us that all forms of protoplasm consist of carbon, hydrogen, oxygen, and nitrogen “in very complex union,” he continues, “To this complex combination, the nature of which has never been determined with exactness, the name of protein has been applied.” This, plainly, is an identification, on Mr. Huxley’s own part, of protoplasm and protein; and what is said of the one being necessarily true of the other, it follows that Mr. Huxley admits the nature of protoplasm never to have been determined with exactness, and that, even in his eyes, the lis is still sub judice. This admission is strengthened by the words, too, “If we use this term” (protein) “with such caution as may properly arise out of our comparative ignorance of the things for which it stands;” which entitle us to recommend, in consequence “of our comparative ignorance of the things for which it stands,” “caution” in the use of the term protoplasm. In such a state of the case we cannot wonder that Mr. Huxley’s own conclusion here is: Therefore “all living matter is more or less albuminoid.” All living matter is more or less albuminoid! That, indeed, is the single conclusion of Mr. Huxley’s whole industry; but it is a conclusion that, far from requiring the intervention of protoplasm, had been reached long before the word itself had been, in this connection, used.
It is in this way, then, that Mr. Huxley can be adduced in refutation of himself; and I think his resort to an epigram of Goethe’s for reduction of the powers of man to those of contraction, digestion, and reproduction, can be regarded as an admission to the same effect. The epigram runs thus:—
“Warum treibt sich das Volk so, und schreit? Es will sich ernähren,