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alliance of instinct with intelligence.* So the jackdaws of Selbourn, according to Mr. White, not finding a sufficiency of towers and steeples, and lofty houses, on which they usually hung their nests in this pleasant village, accommodated themselves to the occasion, and built them in forsaken rabbitburrows. The ostrich is accused of a total want of natural feeling, because she abandons her eggs to be hatched by the heat of the sun: when incubation is necessary, however, the ostrich instinctively employs it, and that, too, in conjunction with an intelligence which is rarely evinced by other birds. Thus in Senegal, where the heat is still great, she relinquishes her eggs during the day, but sits upon them through the night; and at the Cape of Good Hope, where the heat is less considerable, she sits upon them, like other birds, both day and night. In like manner ducks and geese, though not renowned for sagacity, cover up their eggs when they quit them, till their return to the nest; and there are few birds that do not turn and shift their eggs at different periods of the tedious process of incubation, so as to give an equal degree of warmth to every part. We have already observed, however, that the accommodating power of the instinctive principle to particular circumstances, which so wonderfully enables it to supply the place of reason, gives it, in many instances, a striking assumption of its character. It is, hence, possible that one or two of the examples here noticed may be referrible to this accommodating faculty; but the exercise of a certain extent of reason, as a distinct principle, must be admitted in several of them, in which there is not only a display of design and contrivance towards the accomplishment of this new object, but apparently of design and contrivance as the result of a general convention and discussion of the question submitted to the tribe assembled on the occasion, and whose common interest is at stake. Generally speaking, the principle of instinct is perfect and infallible in its guidance; there is, however, an occasional aberration, perhaps a playfulness, in this as in every other part of nature. Thus the light of the candle is, by flies and various other insects, mistaken for the light and warmth of the sun, often to the loss of limb or even life itself. So the flesh-fly and blow-fly (musca carnifica and m. vomitoria) are deceived by the smell of the carrionflower (stapelia hirsuta), and often deposite their eggs upon it instead of upon putrescent meat; in consequence of which the grubs die almost as soon as hatched, for want of proper nourishment. In like manner we find, occasionally, a few migrating birds in countries where they were never seen before, and which have evidently mistaken their course. There are various instincts, connected, for the most part, with a singularity of configuration, that are either peculiar to the birds, or altogether anomalous. But they show, at least, that the great Author of nature is the lord and not the slave of his own laws, and is at all times capable of producing definite effects by a diversity of means. Thus the didus solitarius, or solitary dodo, in general esteemed almost as stupid a bird as the ostrich, divides the labour of incubation with his female, and alternately sits upon the eggs during her absence. The hen of this tribe has a protuberance on each side the breast, like the teat of quadrupeds. When the young of the turtle-dove are hatched, and capable of receiving nutriment from the crop of the mother, the male parent experiences an equal change and enlargement in this organ, secretes the same nutritive material, and equally contributes to the support of its nestlings. I have already observed that insects in general deposite their eggs in places admirably suited to the future wants of the nascent larves, and then forever take leave of their embryo progeny: but the forficula auricxdaria, or common ear-wig, broods over her young like a hen, and only quits them at night, which is the usual period in which this genus flies in pursuit of food or

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Among migrating birds it is not very uncommon for the males alone to dare the dangers of a distant voyage, and to leave the females behind them: but in the fringilla Calebs, or chaffinch, we find this rule completely inverted; for the female chaffinches of Sweden quit their males and migrate to Holland towards the winter, and duly return to them in the spring; while many of the males indulge in a profound sleep during the greater period of their absence. Most vegetables indulge in a winter-sleep of the same kind; but there are some that sleep still longer. Thus the tuberose root of the ferraria Ferrariola, an ornamental herbaceous plant of the Cape of Good Hope, remains torpid every alternate year, and sometimes continues in this state for two years together, without putting forth either leaf or fibre. Let us close these observations with a momentary glance at the very singular instinctive powers of the cancer ruricola, or land-crab. This is an inhabitant of the tropical regions, and especially of the Bahama islands: it is gregarious, and associates in large bodies that preserve an orderly society, for the most part, in the recesses of inland mountains, though they regularly once a year march down to the seaside in an army of some millions, to depositc their spawn in the ocean. The time selected for this expedition is usually the month of May, when they sally forth from the stumps of hollow trees, the clefts of rocks, and subterranean burrows, in enormous multitudes. The whole ground, indeed, is covered with this reptile band of adventurers; and no geometrician could direct them to their destined station by a shorter course. They turn neither to the right hand nor to the left, whatever be the obstacles that intervene: and if they meet with a house they will rather attempt to scale the walls than relinquish the unbroken tenor of their way. Occasionally, however, they are obliged to conform to the face of the country; and if it be intersected by rivers, they pursue the stream to its fountain head. In great dearth of rain they are compelled to halt, when they seek the most convenient encampment and remain there till the weather changes. They make a similar halt when the sun shines with intense heat, and wait for the cool of the evening. The journey often takes them up three months before they arrive on the seacoast; as soon as they accomplish which, they plunge into the water, shake off their spawn upon the sands, which they leave to nature to mature and vivify, and immediately measure back their steps to the mountains. The spawn, thus abandoned, are not left to perish: the soft sands afford them a proper nidus; the heat of the sun, and the water, give them a birth; when millions of little crabs are seen crawling to the shore and exploring their way to the interior of the country, and thus quitting their elementary and native habitation, for a new and untried mode of existence. It is the marvellous power of instinct that alone directs them, as it directed the parent hosts from whom they have proceeded; that marvellous power which is co-extensive with the wide range of organic life, universally recognised, though void of sensation; consummately skilful, though destitute of intelligence; demanding no growth or developement of faculties, but mature and perfect from its first formation. The general corollary resulting from these observations is as follows: that instinct, as 1 have already defined it to be, is the operation of the principle of organized life by the exercise of certain natural powers, directed to the present or future good of the individual; while reason is the operation of the principle of intellectual life by the exercise of certain acquired powers directed to the same object: that it appertains to the whole organized mass, as gravitation does to the whole unorganized; equally actuating the smallest and the largest portions, the minutest particles and the bulkiest systems; every organ and every part of every organ, whether solid or fluid, so long as it continues alive: that, like gravitation, it exhibits, under particular circumstances, different modifications, different powers, and different effects; but that, like gravitation, too, it is subject to its own division of laws, to which, under definite circumstances, it adheres without the smallest deviation; and that its sole and uniform aim, whether acting generally or locally, is that of perfection, preservation, or reproduction.

,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.

ON SYMPATHY AND FASCINATION.

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 endowments 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 dieecous 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 whole process 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 Jintiar, 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, " the poison 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

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