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Of its mode of existence we know nothing: but as little do we know of the principle of gravitation or of mind. We can only assure ourselves that they are distinct powers, perhaps distinct essences; and we see them acting, as well separately as conjointly, for the general good. Under their accordant influence we behold the plastic and mysterious substance of matter, which we must be especially careful not to confound with themselves, rising from "airy nothing" into entity; ascending from invisible elements into worlds and systems of worlds; from shapeless chaos and confusion, into form, and order, and harmony; from brute and lifeless immobility, into energy and activity; into a display of instinct, feeling, perception; of being, and beauty, and happiness. One common design, one uniform code of laws, equally simple and majestic, equally local and comprehensive, pervades, informs, unites, and consummates the whole. The effect, then, being one, the mighty cause that produced it must be one also; an eternal and infinite unity—the radiating fountain of all possible perfections—ever active, but ever at rest— ever present, though never seen—immaterial, incorporeal, ineffable: but the source of all matter, of all mind, of all existences, and all modes of existence. Whatever we behold is God—all nature is his awful temple—all sciences the porticoes that open to it: and the chief duty of philosophy is to conduct us to his altar; to render all our attainments, which are the bounteous afflations of his spirit, subservient to his glory; and to engrave on the tablet of our hearts this great accordant motto of all natural and all revealed religion, of Athens and of Antioch, of Aratus and of St. Paul, " in him we live, and move, and have our being."

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"-''-> LECTURE VI.


We have now summarily contemplated several of the most important phenomena both of organic and inorganic nature; and have traced out something of the laws by which these phenomena are produced and regulated. Among the most extraordinary facts that have occurred to us may, perhaps, be enumerated the occasional production of effects by causes which do not appear to be immediately connected with them; the operation of one body upon another remotely situated, and which, so far as we are able to trace them, have no medium of communication. The sun is perpetually acting upon and influencing the earth, the earth the moon, the moon the ocean: the magnet operates upon iron, whatever be the sheet of substance interposed; and if the iron be divided into small filings, so that the different particles may move with facility, communicates to each an obvious polarity, and gives to the whole a peculiar and beautiful arrangement. And the repulsive and attractive powers of the electric fluid are supposed to act upon each other, not only where two or more particles of this fluid are perfectly or very nearly in contact, but between all particles of it, at all distances, whatever obstacles may lie between them.f

Chemical science lays open to us a wonderful field of similar affections and affinities. Within the range of its peculiar regions, we behold almost every substance evincing a determinate series both of inclinations and of antipathies, strongly attracted by one kind of material, indifferent towards a second, and powerfully avoiding a third. From these extraordinary evidowments proceeds unquestionably the union or separation of different oodies,

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according to the nature of the endowments that are called into action; but their influence, in perhaps every case, commences before such bodies are in a state of contact, and in many cases while they are at a considerable distance from each other.

From lifeless and inorganic matter these peculiar and mysterious affections ascend to vegetable life, and display to us germs, molecules, and fibrils, uniting not at random with germs, molecules, and fibrils, but each selecting the other, and occasionally attracting them from remote situations, the female male, and the male female rudiments; and this with the nicest discrimination of their various powers of crassitude or tenuity, and, consequently, of reciprocal adaptation, without which no vital entity would ensue. Perhaps one of the most extraordinary instances of this kind we are acquainted with exists in the valisneria spiralis, an aquatic and direcous plant, or one belonging to that class in which the male and the female are distinct individuals. The male has a long spiral stem, by which its flower is enabled at all times to adapt itself to the surface of the water, from the bottom of which the plant shoots forth, and to float in the middle of tide-streams of almost every variation of ascent. The stem of the female is straight, and much shorter; and is hence only found in shallow waters, or on shores, where the tide exerts but little influence. Thus differently formed and remotely situated, how is that union to take place, without which there could be no increment, and the valisneria would be blotted out of the book of vegetable life. The wholeprocess is wonderful; a part of it is obvious, but the rest is concealed. As soon as the male flower is become perfected, the spriral stem dries away, and the flower separates itself from it, and sails gallantly over the water in pursuit of the female, for the most part driven, indeed, by a current of the wind or of the stream; yet as soon as it arrives within a certain range of the female, it obeys a new influence, and is attracted towards it in various instances even in opposition to wind and tide, the powers that have hitherto directed it. What, now, is this stupendous influence that thus operates at a distance, and gives to the male flower a new direction? It may possibly be a peculiar kind of odour or aroma; and, perhaps, this is the most philosophical way of accounting for the fact: but however philosophical, it is altogether hypothetical, for we are incapable of ascertaining, and know nothing of the existence of any such exhalation; and could we detect it, we should be still totally ignorant of its mode of operation.

The same curious phenomena seem not unfrequently to take place in the animal system: for here also we can truly affirm that bodies appear to act where they are not, and where we can trace no communicating medium. A small laceration on one of the fingers, sometimes in our own country, but far more frequently in warmer climates, will produce, if unattended to, the disease of a locked jaw; and an inflammation or abscess of the liver a severe pain in the left shoulder. Yet in both these cases we are not distinctly acquainted with any closer connexion subsisting between the finger and the jaw, or the liver and the left shoulder, than there is between these different organs and any other part of the system. We may theorize upon the nature of the communication, but we have no certain knowledge.

The same fact is strikingly exemplified in the different operations of different poisons when introduced into the stomach. Thus it has been observed by Mr. Brodie, in a valuable and ingenious paper, published in the Philosophical Transactions for 1811, that the infusion of tobacco, applied to any part of the alimentary canal, almost instantaneously, and apparently by some other means than that of the circulation of the blood, destroys the action of the heart, and consequently stops the pulsation, while the brain and the other muscles of the system, besides the heart, are comparatively but little affected: and that alcohol, on the contrary, the essential oil of almonds, and the juice of aconite, destroy as rapidly the action of the brain, and throw the animal into violent convulsions, laborious respiration, and deadly stupor, while the heart continues its usual or nearly its usual pulsation, not only during the whole of the symptoms, but for some minutes after death has actually taken place. The woorara, perhaps a species of ticunas, with which the Indians of Guiana poison the points of their arrows, produces the same effect, when inserted into a wound, as aconite juice introduced into the stomach: it operates almost entirely upon the organ of the brain, and more rapidly than it could arrive there by the course of the circulation. The upas Antiar, the anthiar Toxicaria of Leschenaut, on the contrary, one of the most fatal vegetable poisons of the island of Java, produces death when inserted into a wound, not by affecting the brain, but, like the infusion of tobacco in the stomach, by destroying the action of the heart.

In like manner, the poison of the cerastes, or horned snake, though so fatal in a few hours, often in a few minutes when received by a wound, seems to produce little or no effect when tasted and swallowed. "It is clear," says Bruce, "thepoison has no activity, till through some sore or wound it is admitted into circulation.* And a German physician (continues he) was bold enough to distil the pus or putrid matter flowing from the ulcer of a person infected by the plague,and taste it afterward without bad consequences."

Of the immediate cause or nature of this diversity of influence—this discrepancy of action between remote organs, we know no more than we do of the cause or nature of gravitation, of magnetism, or electricity. It has been denominated, indeed, sympathy, fellow-feeling, or consent of parts, in the general language of physiological writers; and so long as we employ these terms merely to import a definite kind or peculiarity of impulse, they may have their use and convenience; but they convey no knowledge, and ought not to be allowed, as I am afraid they sometimes are, to supply the place of knowledge. That the muscles of the jaw-bone sometimes associate in their action with the muscles of the hand or foot; the organ of the left shoulder with that of the liver; and the stomach, under some kinds of stimulus, with the brain; under others with the heart; and under a third sort, as all those that excite nausea, with the skin; while the skin, in return, associates very generally with the action of the kidneys, are ascertained and well-established facts; but why they should be facts, or by what power or medium the association is maintained, we are altogether ignorant.

When the circulation of the blood was first discovered, it was supposed that all these anomalies might fall within the range of this admirable mechanism, and might be explained by its operation. Not one of them, however, is capable of such an explanation. Nor is even the diffused redness which uniformly takes place around the nucleus of an inflamed part in any degree more intelligible or more referrible to this principle; since, in consequence of the device of a circulating system, the vessels in the immediate vicinity of each other are as much cut off from all direct communication as those at the remotest distance; and only, so far as we are able to trace by ocular experiment, associate by the common current of the blood. That they do, in fact, associate by other means we know; but it is by means altogether concealed from us: it is by what, as already observed, we call sympathy or fellowfeeling; but what we only call so to express a peculiarity of action, the cause of which we are incapable of penetrating.

There is one curious and highly important discovery in the animal economy, however, that has been made, or rather completely established, within the last two or three years, which seems to show that such associate action of parts, at a distance from each other, may be the result of a direct intercourse or medium of communication, though the connecting channel is too subtile for pursuit: for it seems now to be ascertained, as it had, indeed, been long suspected, though without the proof of actual experiment, that a variety of substances pass from the stomach into the kidneys, apparently without entering into the circulation of the blood, by an unknown and even a much shorter course. Now, to the eye of the anatomist, there are no organs more distinct from each other; they not only lie far remote in situation, but even in different cavities, and are separated by a strong, stout membrane, called the peritoneum.

* Appendix to Travels, p. 301, Svo. edition

To determine whether such a channel actually existed or not, Dr. Wollaston introduced into the stomach three grains and a half of the salt called prussiate of potash; the presence of which, in almost all kinds of colourless fluids, is capable of detection to the utmost nicety, by mixing with them a small portion of solution of iron, the colourless compound being immediately marked with a blue tinge. The above quantity was given to a healthy person, about thirty-four years of age, and was repeated every hour to the third time. The natural secretion from the kidneys being tested every half hour, was found in two hours to be slightly dyed, and at the end of four hours to afford a deep blue. At this period, just one hour after taking the last dose, and when the blood-vessels might be supposed to be fully impregnated with the material, if it passed to the kidneys through this conveyance, blood was taken from the arm, and allowed to coagulate, so that the serum or limpid part of it might be fully separated. The presence of the prussiate was then endeavoured to be discovered, by means of the solution of iron, but without the leasteffect, for the serum still remained colourless. And in other experiments of a similar kind, made both by Dr. Wollaston and Dr. Marcet, it was satisfactorily ascertained that the prussiate of potash, though it found its way readily to the kidneys, did not exhibit any trace of its existence in the fluid of any other organ whatever, any more than in that of the blood; as the saliva, the mucus of the nostrils, or the limpid discharge produced by blisters. Mr. Home has since shown, that rhubarb introduced into the stomach in like manner finds a path to the kidneys, apparently without passing through the circulating system.*

Mr. Home at one time suspected that the organ of the spleen afforded a passage from the stomach to the circulation of the blood in the cases before us, instead of the lacteal vessels, which immediately rise from the alimentary canal. This idea, he has, however, since relinquished as erroneous; but had even such a passage existed, it would not have answered the purpose; for it would only have conducted materials by another path to the blood; and the experiments of Dr. Wollaston have sufficiently proved, that the unknown channel, wherever it lies, has no connexion whatever with any part of the system of blood-vessels, or even with the common system of absorbent vessels: and so far he seems to have disproved a previous theory of Mr. Charles Darwin upon this subject, which held, that the absorbent system might become the channel, by assuming a retrograde action. Such action, however, has never been established, and, independently of the experiments before us, it is rendered highly inconceivable by the known structure of the absorbent vessels themselves.

The corollary, then, resulting from these observations, is, that in the animal system, as well as in inorganic nature, bodies in various instances act where they are not, and through channels of influence or communication, with which we are altogether unacquainted.

The examples thus far offered, in regard to animals, I readily admit, are taken from different parts of the same individual frame: but as they are drawn from parts remotely situated, and whose intercourse, so far as we are able to trace it, is as much cut off as though they were of different frames, excepting, indeed, by a channel which does not show itself to be resorted to in the cases before us, I mean the blood; they may serve to lay a groundwork for our conceiving the possibility of a similar influence or association of action between different parts of different frames, or, which is the same thing, between living body and living body.

I proceed, then, to offer examples of this latter kind of influence. The subject, I am aware, is not only of a very curious, but of a very delicate nature,

* The only mode by which the present writer win conjecture the possibility of these substances being conveyed to the kidneys by the course of the blood, and becoming manifest in their ordinary secretion, on the application of chemical tests, is, that they may be so minutely decomposed by the action of the blood while passing through it, as to be beyond the influence of any tests whatever; and that they only discover themselves in the renal secretion, in consequence of a peculiar attraction or affinity of the organ for such materials, and their being hereby thown oft in a more concentrated fo'nn. But this explanation la, after ail, merely conjectural.—See Study of Med. vol. v. p. Se3, Sd edition.

and requires to be handled with the greatest dexterity; nor do I know of any philosophical work to which we can turn as a proper beacon to direct us in our pursuit, and to determine where the boundary of sober judgment ceases, and that of imagination begins.

Some of the instances I shall refer to may, perhaps, be denominated instinctive influences. I have no objection to the term; but the facts will remain as singular, and as little accounted for, as if no such term were in existence.

Among quadrupeds, and, so far as we know of them, among amphibials, fishes, and insects, there exists but little attachment of the male to the female during the time of parturition, or to his own young after the female has brought them forth. The seal-tribes, and especially those of the trichecus Afamatus, or lamantin, from which we have probably derived all the idle stories of mermen and mermaids, together with a few others, may, perhaps, be offered as an exception; for these, and especially the lamantin, form unions of single male with single female that continue through life, and live in distinct families with their offspring, till the last, acquiring maturity, leave their paternal home, and found similar families for themselves. Such, then, being the general fact with regard to other animals, whence comes it to pass that the males among the bird-tribes should evince, with a few exceptions, an attachment that is so rarely to be met with elsewhere? What is that wonderful power that rivets the greater number of male birds to female birds during the time of nestling and incubation; that impels them to take an equal part in constructing the nest, and stimulates them with feelings unknown at any other season? Whence is it that several of them, as the male raven (corvus Corax), divide the toil and time of sitting, and incubate the eggs by day as the female does by night"? or, that others of them, leaving to their respective females the entire processof incubation, sooth them through the whole of this tedious period, often extending to not less than six or eight weeks, with their melodies from a neighbouring bush, and supply them with food with the utmost tenderness and punctuality?Whence is it, more especially amid birds that feed their young with a viscid chyle or milk, secreted at that peculiar period in the crop or craw, that the crop of the male becomes enlarged and changed in its action, in the very same manner as that of the female, so as to enable him to divide the tender office of nursing, and to supply the young with an equal quantity of nutriment? In the body of the mother we can, perhaps, trace a series of actions which, if they do not give us a full insight into the cause of such a change, and such an additional function, at least prepare us to contemplate it with less astonishment; it is a change, in a very considerable degree, analogous to what occurs in the female frame of most other kinds and classes when similarly situated; and which is evinced in its highest and most beautiful perfection in our own race. But in the production of a similar change in the crop of the male pigeon, we meet with a fact altogether anomalous and alone: there is no connexion of organ with organ; no perceptible chain of actions that can have given rise to it: the frames of the individuals are distinct. It is a pure sympathy excited in one being by a peculiar change produced in the organization of another, and leading to a similar change in the being that is thus most wonderfully and inexplicably operated upon.

Let us pass from the bird-tribes to fishes. There are various animals of this class that, on being touched, or even approached without being touched, are enabled to exhaust the irritable or sensorial power, or both together, of the hand or other limb that approaches them, so as to paralyze it and render it incapable of exertion. Such, especially, are those fishes which we denominate the torpedo-ray, and the electric eel or gymnote. Of these the former has been longest known to naturalists; for, in consequence of its being an inhabitant of the Mediterranean Sea, it is described both by Greek and Roman writers, who impute its distinctive faculty to magic; and conceive that the animal has a power, not only of concentrating this magical energy at option, but if seized hold of by a fishing-hook, of impelling it through the whole

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