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The pain of the self-denial is all one, And what that is, I had rather the reader should believe on my credit, than know from his own trial. He will come to know it, whenever he shall arrive at that state, in which, paradoxical as it may appear, reason shall only visit him through intoxication : for it is a fearful truth, that the intellectual faculties by repeated acts of intemperance may be driven from their orderly sphere of action, their clear day-light ministeries, until they shall be brought at last to depend, for the faint manifestation of their departing energies, upon the returning periods of the fatal madness to which they owe their devastation. The drinking man is never less himself than during his sober intervals. Evil is so far his good.

Behold me then, in the robust period of life, reduced to imbecility and decay. Hear me court my gains, and the profits which I have derived from the midnight cup.

Twelve years ago I was possessed of a healthy frame of mind and body. I was never strong, but I think my constitution (for a weak one) was as happily exempt from the tendency to any malady as it was possible to be. I scarce knew what it was to ail any thing. Now, except .when I am losing myself in a sea of drink, I am never free from those uneasy sensations in head and stomach, which are so much worse to bear than any definite pains or aches.

At that time I was seldom in bed after six in the morning, summer and winter. I awoke refreshed, and seldom without some merry thoughts in my head, or some piece of a song to welcome the new-born day. Now, the first feeling which besets me, after stretching out the hours of recumbence to their last possible extent, is a forecast of the wearisome day that lies before me, with a secret wish that I could have lain on still, or never awaked.

Life itself, my waking life, has much of the confusion, the trouble, and obscure perplexity, of an ill dream. In the day time I stumble upon dark mountains.

Business, which, though never particularly adapted to my nature, yet as something of necessity to be gone through, and therefore best undertaken with cheerfulness, I used to enter upon with some degree of alacrity, now wearies, affrights, perplexes me. I fancy all sorts of discouragements, and am ready to give up an occupation which gives me bread, from a harassing conceit of incapacity. The slightest commission given me by a friend, or any small duty which I have to perform for myself, as giving orders to a tradesman, &c. haunts me as a labour impossible to be got through. So much the springs of action are broken.

The same cowardice attends me in all my intercourse with mankind. I dare not promise that a friend's honour, or his cause, would be safe in my keeping, if I were put to the expense of any manly resolution in defending it. So much the springs of moral action are deadened within me.

My favourite occupations in times past, now cease to entertain. I can do nothing readily. Application for ever so short a time kills me. This poor abstract of my condition was penned at long intervals, with scarcely any attempt at connexion of thought, which is now difficult to me.

The noble passages which formerly delighted me in history or poetic fiction, now only draw a few weak tears, allied to dotage. My broken and dispirited nature seems to sink before any thing great and admirable.

I perpetually catch myself in tears, for any cause, or none. It is inexpressible how much this infirmity adds to a sense of shame, and a general feeling of deterioration.

These are some of the instances, concerning which I can say with truth, that it was not always so with me. Shall I lift

up
the veil of

my
weakness

any

further ? or is this disclosure sufficient ?

I am a poor nameless egotist, who have no vanity to consult by these Confessions. I know not whether I shall be laughed at, or heard seriously. Such as they are, I commend them to the reader's attention, if he finds his own case any way touched. I have told him what I am come to. Let him stop in time.

ELIA

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FROM THE JOURNAL OF SCIENCE. 3 Review of some of the General Principles of Physiology, with the

Practical Results to which they have led. By A. P. W. Philip, M. D. F.R.S. Edinb.

We are now to direct our attention to the phenomena of the nervous system. Under this term is generally included the sensorial as well as nervous system, properly so called. From a careful review of the functions of these systems, however, it will appear, I think, that they do not differ less from each other than from the muscular system.

M. le Gallois, as far as I know, is the only author who has endeavoured by experiments to draw a line of distinction between them. It is unnecessary, however, to examine the opinion he has advanced, as many of the facts which I shall have occasion to state will be found incompatible with it. After reviewing the phenomena of the nervous system, properly so called, we shall be better prepared to enter on this question.

The functions of the nervous are much more complicated than those of the inuscular system. The first we shall consider is one on which I have already been necessarily led to make some observations. We have seen that the influence of the nervous system is the only stimulus of the muscles of voluntary motion, and that it is also capable of exciting those of involuntary motion, although in their usual functions the latter are excited by other means. Here the question arises, if the nervous system be not concerned in the usual functions of these muscles, why are they universally subjected to its influence? This question we are not prepared to consider till we have taken a view of some of the other functions of the nervous system; but the influence of that system not only does not excite the muscles of involuntary motion in their usual functions, but, as I have already had occasion to observe, is communicated to them in way different from that in which it is communicated to the muscles of voluntary motion. We shall here inquire in what this difference consists.

The following positions have been ascertained by repeated experiments. Chemical agents, applied to the brain and spinal marrow, more powerfully influenced the heart than mechanical agents, while the latter influence the muscles of voluntary motion more than chemical agents. Both, applied to the brain and spinal marrow, excite the heart after they cease to produce any effect on the muscles of volun- . tary motion. Applied to any part of the brain and spinal marrow, they affect the action of the heart, while the muscles of voluntary motion are only affected when they are applied to the parts from which the nerves of those muscles originate. Applied to the brain and spinal marrow, they never excite irregular action in the heart, while nothing can be more irregular than the action they excite in the muscles of voluntary motion. Their effect on these muscles is felt chiefly on their first application, but continues on the heart, within certain limits, as long as they are applied. These differences in the effects of agents applied to the brain and spinal marrow must, it is evident, be explained, before we can understand the relation which subsists between the nervous and muscular systems.

It appeared to me probable, from the result of several experiments, that the cause of chemical agents, applied to the brain and spinal marrow, producing a greater effect on the heart than those which act mechanically is, that the former, from their nature, act on a larger surface. If this opinion be correct, the mechanical agent, it is evident, may be rendered the most powerful, by confining the chemical to a smaller space than it occupies, which was found from frequently repeated experiments to be the case.

Most of the experiments on this part of the subject, it may be observed, as well as many to which I have already referred, were made, not on the living, but newly dead animal, which was always employed if the nature of the experiment admitted of it.*

It appeared, from repeated experiments, that neither chemical nor mechanical agents, applied to the brain and spinal marrow, affect the action of the heart, unless they make their impression on a large portion of these organs. Every part of them may be stimulated individually, without the action of the heart being influenced; and the agent being the same, its influence on this organ is always proportioned to the extent of surface to which it is applied. It does not appear that it is of much importance on what part of the brain the agent makes its impression. Even stimulating the surface alone, either mechanically or chemically, immediately increases the action of the heart.

Another circumstance, which appears to be of great consequence in explaining the difference of the effects of agents applied to the brain and spinal marrow on the two sets of muscles, is, that the heart obeys a much less powerful stimulus than the muscles of voluntary motion do. The most powerful chemical agents alone affected them, while all that were tried readily influenced the action of the heart. Mechanical agents which, by bruising and dividing the parts, occasion the greatest possible irritation, are best fitted to excite the muscles of voluntary motion. Chemical agents, indeed, from their effects on the heart, we should, at first view, consider the most powerful. But their greater effect on this organ is readily explained by what has just been said. When the effect of the mechanical agent was rendered extreme

Why the newly dead animal is as good a subject for many physiological experiments as the living one, will appear from what I shall afterwards have occasion to lay before the reader.

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and general, its influence on the heart was found much greater than that of any chemical agent which was tried. We have seen that suddenly crushing any considerable portion of the brain or spinal marrow instantly destroys the function of that organ.

The conclusions, then, at which we arrive are, that the heart is influenced by all agents applied to any considerable part of the brain or spinal marrow, while the muscles of voluntary motion are only infuenced by the more powerful agents applied to certain small parts of them.

These facts being ascertained, the other differences observed in the effects of agents applied to the brain and spinal marrow on the heart and muscles of voluntary motion are easily explained.

Irregular action of a muscle arises from stimuli acting partially or at intervals on its nerves, or on the part of the brain or spinal marrow from which its nerves arise; but very partial action of an agent on these organs, we bave just seen, is incapable of exciting the heart; and while the agent is applied to any part of them, as all their parts seem equally to influence the heart, it cannot act upon it interruptedly, as an instrument does on the muscles of voluntary motion, when it is moved from place to place in the brain.*

The heart feels the effect of the agent within certain limits, as long as it is applied to the brain and spinal marrow, while the muscles of voluntary motion chiefly feel its first impression; because they feel only the effects of powerful agents, applied to certain small parts of these organs, which, being strongly impressed, soon lose their excitability; while the heart feels the sum of all, even slight impressions, made on every part of them.

It also appears, from what has been said, why those who have endeavoured to influence the heart by stimulating the small parts of the brain from which its nerves seem chiefly to originate, have failed ; and why the heart may be influenced through this organ and the spinal marrow, after their power is too far reduced to excite the muscles of voluntary motion. As these only obey agents applied to one part, if the change there be not sufficiently great to produce the effect, it can be assisted by no other. Thus I have found by experiment, that a blow which affects the brain generally, without materially injuring it, produces comparatively little effect on the muscles of volúntary motion; but it produces a great effect on the heart, because it feels the sum of all the impressions. The nervous system, therefore, may be so far exhausted as not to admit of the vivid impressions necessary to excite the muscles of voluntary motion, and yet capable of those which influence the heart.

The heart, however, is not the only organ which receives nervous influence from every part of the brain and spinal marrow. The power of the blood vessels, we have seen, may be destroyed by the sudden

* It is true, that although the heart is only influenced by agents applied to a large portion of the brain, we may conceive them so applied as to produce irregular action in it, and we find that certain irritations of the nervous system have this effect. Suddenly crushing part of the brain or spinal marrow renders the action of the heart irregular. But it is evident that the heart, not being subject to agents whose action is confined to a small portion of these organs, and being equally affected through all parts of them, must render it much less subject to irregular action, and readily accounts for this not having been observed in the experiments just referred to.

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destruction of either of these organs, and it also appears, from direct experiments, that they may be influenced, even in the extremities, by agents applied even to the upper surface of the brain. The alimentary canal may also be influenced through both the brain and spinal

From the extreme irregularity of the motions of this canal, we cannot ascertain whether it is subject to the influence of the different parts of the brain and spinal marrow, in the way in which this was done respecting the heart and blood vessels. I therefore endeavoured to ascertain this point by experiments of a different kind; from which it appears, that on withdrawing a great part of the influence of either the brain or spinal marrow, the stomach is affected in a way which I shall soon have occasion to consider more particularly.

We may easily conceive why the muscles of voluntary motion are excited when those parts of the brain or spinal marrow from which they receive their nerves are stimulated; þut it seems at first view more difficult to account for the heart and other muscles of involuntary motion being subject to the influence of every part of these organs. We cannot suppose that they receive nerves from every part of thema We know, ideed, that no organ does so. The following seems to be the state of the question. We see some parts influenced by every part of the brain and spinal marrow; others only by small parts of them. In the latter instances, we see directly proceeding from those small parts of the nerves of the part influenced. In the former instance, namely, where the part is influenced by all parts of the brain and spinal marrow, we do not see nerves going directly from all parts of these organs to the part influenced, but we see this part receiving nerves from a chain of ganglions to which nerves from all parts of them are sent. It is, therefore, evident from direct experiments, that the nerves issuing from ganglions convey to the parts, to which they send nerves, the influence of all the nerves which are received by these bodies.

Such then is the relation which the most important organs of involuntary motion, bear to the brain and spinal marrow. Their powers are not directly dependant on either, yet they are subjected to the influence of every part of both, communicated through the medium of the ganglions; and when we see the other organs of involuntary motion equally independent of the brain and spinal marrow, and supplied with nerves from ganglions, in the same way with the former, it is impossible not to infer, that they bear the same relation to the nervous system. Thus, it would appear, that the ganglions may be regarded as a secondary centre of nervous influence, receiving supplies from all parts of the brain and spinal marrow, and sending to certain organs the influence of all those parts.

If the nervous influence of the thoracic and abdominal viscera be thus supplied from a common source, why, in affections of the spinal marrow, it may be asked, is the breathing most influenced when the

, disease is in the dorsal portion of this organ, and the action of the bladder and rectum, when its chief seat is in the lumbar portion? This necessarily arises from the intercostal muscles deriving their nerves from the dorsal, and the abdominal muscles from the lumbar portion of the spinal marrow. The latter muscles generally excite, or, at least, increase, the action of the bladder and rectum, by pressing them against their contents, and also by this pressure contribute mechani

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