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versal, or powerful, for a vivifying principle. With a mind like his, capable of looking through nature, up to nature's God, so sad a delusion had no affinity. His words upon the subject are the following. After alluding to the resemblance of the shock of the Gymnotus Electricus, and of the Torpedo, to the Voltaic, he says, "It has been conceived that other phenomena of living action may be connected with the operation of weak electrical powers, such as secretion; and some ingenious hints, on this subject, have been advanced by Dr. Wollaston and Mr. Home, and some experiments, relating to the subject, instituted by Mr. Brande. Such inquiries are worthy of further pursuit, as they may tend to elucidate some important functions of the animal economy; but they must not be confounded with certain vague speculations, that have been advanced by some authors, on the general dependence of nervous or sensitive action, and muscular or irritable action, upon electricity. Such speculations are mere associations of words, derived from known phenomena, and applied illogically to unknown things. The laws of dead and living nature appear to be perfectly distinct; material powers are made subservient to the purposes of life, and the elements of matter are newly arranged in living organs; but they are merely the instruments of a superior principle."—(Elements of Chemical Philosophy, p. 175.) There can be nothing in philosophy more sound than this. If, therefore, we may safely admit, with John Hunter and Abernethy, that, in addition to the visible fabric of our bodies, there is an invisible something, whether it be

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electricity or not, connected with their vital functions, and especially ministerial to the functions of the nervous system; we must stop here. We have no data for considering this invisible something, life, however powerful, however agile, or however universal it may be. We cannot breathe without air; without blood we cannot be nourished; without electricity, it may be, the functions of the nervous system, of that system which forms the intermediate link between the sentient and material parts of the animal frame, cannot proceed. But to speak of life as identical with either, or with all these, or to assert that sensation may depend, as the materialists dream, on organization, is altogether, as Sir Humphry Davy says, illogical—not to use a harsher epithet.

The phenomena of the Torpedo, and of the Gymnotus Electricus, to which both he and Abernethy have alluded, in illustration of their respective opinions, serve but to show that, in such instances at least, electricity is a defensive provision of the Creator, subject to the instincts of these animals. But the principle of life how are we to discover, appertaining as it does to the " secret things" known only to Him that liveth for ever and ever; who created the heaven, and the earth, and the sea, and all creatures and things that are therein ?—(Deut. xxix. 29; Rev. x. 6.)

Still the endeavour to prepare the bewildered mind of the Materialist for the reception of revealed truths, by arguments founded on facts derived from the investigation of natural phenomena, was considered highly praiseworthy by Abernethy, who has assigned the following conclusive

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reasons for believing that the brain is undoubtedly the organ, or congeries of organs, of sensation and volition.

1st. If the continuity of a nerve be intercepted at any point between the extremity which receives impressions from the objects of sense and the brain, both feeling and volition by means of that nerve are suspended.

2dly. If a certain degree of pressure be made upon the brain, both feeling and voluntary motion cease whilst it continues, and return when it is removed.

3dly. We have evidence that the perceptions and intellect of animals increase in proportion as the brain becomes larger and more complex; and therefore we have reason to conclude that these faculties are connected with that part of the nervous system.

4thly. The conviction which we generally experience, that feeling exists in the part which receives impressions, is shown to be deceptive by the following facts:—

If a nerve be irritated midway between the brain and its extremities, pain is supposed to be felt in those extremities; and, if it supplies muscles, those muscles become convulsed. In like manner, persons who have had their limbs amputated can scarcely believe that they are removed, on account of the pain and other sensations which they still appear to feel in them. A man has even been known to scratch his wooden leg.

If, then, it must be admitted that the brain is the organ of sensation, and that the mandates of the will proceed from thence; the question naturally occurs, By what animal process is the impression thus given to the brain from the tangible extremity? Gross impulse will afford no explanation, since a person may have a leg shot off without feeling it, and fall to the ground, not knowing why. The subtlety, likewise, of many objects of our perceptions, and, more than all, the phenomena of ocular spectra, forbid such a supposition. Is it not more likely that sensation is the result of concatenated motions,—of motions first excited in the tangible extremity, and thence imparted with inconceivable celerity to the brain? Such is the celerity, that, if the foot receive a blow, it is instantly withdrawn: yet there must have been previously a twofold action; first, from the foot to the sensorium, causing sensation; and, secondly, from the brain to the muscles, causing action." Can this be otherwise accounted for, Abernethy asks, than on the principle of a fluid of the most exquisite subtlety and mobility? Probably not. The objection is not to such a supposition, but to making any such fluid identical with life. The conclusion at which he himself arrives, in common with most reflecting persons, of all ages, and in conformity, as he says, with the suggestions of modern physiology, is, that in the human body there exists an assemblage of organs formed of common inert matter, such as we see after death; a principle of life and action; and a sentient and rational faculty (the soul), all intimately connected, yet each apparently distinct from the other. Failure, or disturbance of the actions of life, may prevent or disturb our feelings, and enfeeble, perplex, or distract our intellect; whilst the mind equally affects the actions of life, and so influences the whole body. Terror seems to paralyze all

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its parts; and the contrary emotions cause the limbs to struggle and become contracted from energy. Still, however, these facts may countenance the idea of the identity of the mental and vital principles; the reasons, Abernethy contends, for believing them to be distinct, are irresistible."Whilst, therefore, I feel interested," he says, "in oppugning, on the one hand, those physiological opinions which tend to confound life with organization; I would, on the other, equally oppose those which confound perception and intellect with mere vitality. My own mind, he eloquently adds, rests at peace in thinking on the subject of life, as I was taught to think by Mr. Hunter; that it is something, namely, independent of organization, of a subtil, invisible, and highly mobile nature, inhering in and connected with the evident materials of living beings; and I am visionary enough to imagine, that if these opinions should become so established as to be generally admitted by philosophers, that if they once saw reason to believe that life was something of the kind above described, superadded to organization, they would then see equal reason to believe that mind may be superadded to life, as life is to structure. Nay, that they would still further perceive how mind and matter might reciprocally operate on each other, by means of an intervening substance. Thus would physiological researches even enforce the belief which, I may say, is natural to man; that, in addition to his bodily frame, he possesses a sensitive, intelligent, and independent mind; an opinion which tends, in an eminent degree, to produce virtuous, honourable, and usefid actions."

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