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inch posterior to its internal angle. The cerebral matter adhered only round the edge of this opening, &c. The olfactory nerve of the left side was pushed aside towards the mesial line, and at the anterior part of the bulb was, along with a small part of the brain adjoining to it, dark-coloured and softened." This individual, although in a state of coma or delirium during the whole period between the infliction of the injury and his death, is reported to have answered questions distinctly when roused; and his condition is THEREFORE assumed as proving that no connexion subsisted between the preservation of the power of language and integrity of the inferior portion of the anterior lobes. The presence of organic degeneration in the anterior lobes, however, is not sufficient: it must extend to those convolutions resting on the CENTRE of the orbital plate; and moreover, the change must be present on the same spot IN BOTH HEMISPHERES. In Bouillaud's cases, this condition of the brain was observed, and in them the loss of language was complete and permanent. Where the injury is limited to ONE side, as in the case under discussion, we can no more expect that the faculty should be destroyed, than that, from the loss of one eye, blindness should ensue. But supposing for a moment that the softening described had been detected in the right hemisphere likewise, the fact could not have invalidated Dr Gall's conclusions, inasmuch as the change does not appear to have involved the organ of Language at all. It is stated to have been situate half an inch posterior to the internal angle of the orbital plate," and to have included the portion of brain adjoining to the olfactory bulb. Had Dr Moir consulted any of the works treating of the principles which he aspires to oppose, he would have found that the point here indicated corresponds to the organ of Form, and not to that of Language.

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I need not say that this case likewise must be regarded as altogether irrelevant. I am, &c.

MONTROSE, 5th Nov. 1834.

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W. A. F. BROWNE.

ARTICLE XI.

PROXIMATE CAUSE OF SLEEP.:

1. Mr ANDREW CARMICHAEL'S Reconsideration of his " Conjectures" in reference to Mr MACNISH'S " Philosophy of Sleep." Read before the Dublin Phrenological Society.

IN the Phrenological Journal, No. XXXIX, is an able and interesting review of Mr Macnish's "Philosophy of Sleep."

I

participate in every sentiment it expresses of this admirable work. I think it worthy of a place in every well-furnished library;" and I am sure it will interest equally the reader for amusement and the philosophical thinker." But there is one little passage, and, perhaps the only one in the book, or the review, in which I very widely differ from Mr Macnish and the reviewer; and this confession will perhaps be, considered an unqualified compliment to both, as even that passage might not have proved any exception, if it had concerned any other essayist but myself. Be that as it may, I dissent from Mr Macnish, because he confounds the essence of my theory with an inference drawn from it, a corollary, which may be false even though the theory be true; and I dissent from the reviewer, because he adopts the mistake, and judges of me and my hypothesis accordingly. The following paragraph from the Review comprises the whole of the passage to which I have adverted.

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I "In treating of the uses of sleep, the author comments on the views of Mr. Andrew. Carmichael, of which we gave some account at page 268 of this volume. Mr Carmichael, supposes sleep to be the period, when assimilation goes on in the brain. In this respect (says Mr Macnish), I believe that the brain is not differently circumstanced from the rest of the body. There, as elsewhere, the assimilative process proceeds both in the slumber+ ing and in the waking state; but that it is at work in the brain only during sleep, analogy forbids us to admit. So long as circulation continues, a deposition of matter is going on; and cir culation, we all know, is at work in the brain, as in other organs, whether we be asleep or awake.' Mr Carmichael's theory (the Reviewer continues), is certainly an unsupported conjecture, and we are inclined to agree with Mr Macnish in thinking analogy against it."

**

I never proposed my theory as any thing else but a conjecture; but it can scarcely be said to be unsupported, when it naturally accounts for all the various phenomena of sleep, and has stood its ground in defiance of every objection which my own reflections or the ingenuity of others have as yet started against it. My simple hypothesis, divested of all inference or corollary, is this: not that sleep is the period when assimilation goes on in the brain, BUT THAT THE PROCESS OF ASSIMILATION IN THE BRAIN

IS THE ACTUAL CAUSE OF SLEEP.

We know that that must be something more than rest which involves so intense and predominant a change as that which locks up the senses and the intellect, and induces an oblivion of all we knew, an annihilation to us of all that existed. Such a change can only be caused by some important vital process, so indispensable as to be of daily recurrence, and of such general influence as to engage every part of the frame, but particularly the organs

of thinking, sensation, and voluntary motion. Such a process is that which repairs the waste of the brain and nerves, and preserves their consistence and vigour; and powerful and overwhelming must be its effects upon the delicate and fragile instruments of thought, feeling, and motion. It would be, in my mind, irrational to suppose that a change which affects their very structure, by the deposit of new particles, if that deposit be extensive and considerable, must not be attended by a cessation of their functions-an actual, though a natural paralysis-THE

PARALYSIS OF SLEEP.

If small in quantity, and while the brain and nerves are in a state of active energy, the matter deposited may be hurried unobserved into the existing activity of the living matter; but if large in quantity, and while these organs are resting from their labours, can it be that the extraneous and unassimilated mass does not press its increasing weight on their fragile machinery, and produce an EFFECT something like the pressure of the overswollen blood vessels-but natural, necessary, and healthful,what we have already termed THE PARALYSIS of SLEEP?

A large deposit of those particles not yet employed in the functions of feeling or thinking, must have a similar effect as the imposition of an extraneous body on those tender and exquisite organs; and their paralysing compression must continue under the form of sleep until the assimilation is complete, and the new mass of nervous particles as fit as the old for the operations and uses designed by the Creator. The function then commences; internal organ after organ, nerve after nerve, enters into activity; the external senses resume their daily occupations; the mind is in communication with the external world; we are, to all intents and purposes, awake.

In this account of the principal component part of my theory, I have borrowed, in some degree, from my Memoir of Spurzheim. The passages in that work express, with a few exceptions, the views which I still entertain upon this subject. But where those exceptions occur, I have modified my exposition so far as was necessary to convey the opinions I would be now understood to profess. I am indebted to Mr Macnish for forcing upon me the reconsideration of the hypothesis. Neither he nor I can have any object beyond the attainment of truth; and, to this happy result, nothing is more conducive than the collision of minds.

It is not necessary to my theory, that the assimilative process should be at work in the brain only during sleep. It may proceed there, as elsewhere, both in the slumbering and in the waking state, without affecting, in the slightest degree, my hypothesis. But it is necessary to its truth, that there, as elsewhere, this process should operate with more energy, or at least more effect,

during our sleeping than our waking hours; and that this is the fact, appears in many passages of Mr Macnish's own work. "When the body," says Mr Macnish," is in a state of INCREASE, as in the advance from infancy to boyhood, so MUCH SLEEP is required, that the greater portion of existence may be fairly stated to be absorbed in this way. It is not mere repose from action that is capable of recruiting the wasted powers, or restoring the nervous energy. Along with this is required that oblivion of feeling and imagination which is essential to, and which in a great measure constitutes, sleep. But if, in mature years, the body is adding to its bulk by the accumulation of adipose matter, a greater tendency to somnolency occurs than when the powers of the absorbents and exhalants are so balanced as to prevent such accession of bulk *.”

I cannot agree with Mr Macnish in his observation that oblivion of feeling and imagination in a great measure constitutes sleep. Whatever causes sleep, causes also the oblivion with which it is attended. But, to a certain extent, I agree with his subsequent observation, that, while one set of organs is laying down particles, another is taking them up with such exquisite nicety, that, for the continual momentary waste, there is continual momentary repair +. This appears to me to require a little qualification to meet the admitted fact of the " renovating influence of sleep" but I should not dissent from the expression "diurnal waste, and diurnal repair ;"-a form which more accurately connects itself with Mr Macnish's observation, that "this is capable of going on with the strictest equality for half a century ||."

This renovating influence of sleep is more distinctly explained by Mr Macnish, where he remarks" That it increases diges tion, and as a natural consequence nutrition, is rendered probable by many circumstances; hence it is the period in which the regeneration of the body chiefly takes place. Were there even no augmentation given to the assimilative function, as is maintained by Broussais and some other physiologists, it is clear that the body would be more thoroughly nourished than when awake; for all those actions which exhaust it in the latter condition are quiescent, and it remains in a state of rest, silently accumulating power without expending any;" in other words, silently accumulating new particles, or rather masses of particles, without expending the old in the same proportion.

I have already adverted to the effect of this accumulation on the entire brain; and, did space permit, I might notice the consequences of partial release of the brain and nerves from this influence-namely, nightmare, somnambulism, and sleep with

Philosophy of Sleep, 2d edit. p. 4.

+ Id. p. 6.

! Id. p. 5.

+ Id. p. 5.

☛ Id. p. 21.

dreams. There is one condition, however, that ought not to be passed over in silence; that in which the brain and nerves of sense are in a waking state, and the nerves of voluntary motion are still shackled under the weight of the new and unassimilated deposit of the nervous particles. This is a state that but seldom presents itself. These nerves, in our waking moments, appear to be always ready to obey the will, except when they are labouring under paralysis; but the natural paralysis of sleep is so easily dissipated that it rarely can maintain its power after the mind issues its mandate that the limbs shall move. I should have been without an example of this peculiar condition, if Mr Macnish had not furnished me with a most satisfactory instance, in which he himself is delineator, subject, and sufferer.

"During the intensely hot summer of 1825," says this graphic and lively writer, "I experienced an attack of DAY-MARE. Immediately after dinner, I threw myself on my back upon a sofa, and, before I was aware, was seized with difficult respiration, extreme dread, and utter incapability of motion or speech. I could neither move nor cry; while the breath came from my chest in broken and suffocating paroxysms. During all this time, I was perfectly awake; I saw the light glaring in at the windows in broad sultry streams; I felt the intense heat of the day pervading my frame; and heard distinctly the different noises in the street, and even the ticking of my own watch, which I had placed on the cushion beside me. I had, at the same time, the consciousness of flies buzzing around, and settling, with annoying pertinacity, upon my face. During the whole fit, judgment was never for a moment suspended. I felt assured that I laboured under a species of incubus. I even endeavoured to reason myself out of the feeling of dread which filled my mind; and longed, with insufferable ardour, for some one to open the door, and dissolve the spell which bound me in its fetters. The fit did not continue above five minutes: by degrees I recovered the use of speech and motion; and, as soon as they were so far restored as to enable me to call out and move my limbs, it wore insensibly away

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Upon the whole," continues Mr Macnish, " I consider DAYMARE and NIGHTMARE identical. They proceed from the same cause, and must be treated in a similar manner +." It must be admitted that they are nearly, but not altogether, identical. In both, if I am right in my views, the nerves of voluntary motion are under the influence of the new deposit of nervous matIn nightmare the nerves of sense are under the same influence. In daymare they are not; they are perfectly awake, and the individual is in full communication with the external † Id. p. 158.

ter.

Philosophy of Sleep, 2d edit. p. 157.

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