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vening thirty feet of intestine is almost entirely without sensation in ordinary circumstances. The movements of the intestine are kept up by means of the sympathetic system of

nerves.

16. And now with regard to the Feelings of Alimentary action. These are of the pleasurable kind when the action is healthy; disease and disorder bring on a countless multitude of pains.

Discussing first the sensation of taking food, we shall find a pretty general agreement as to its character. I do not speak of the feeling of Taste, but of the sensibility connected more particularly with the stomach, and which extends even to the mouth in connexion with salivation, and is spoken of as the relish. If we include the entire mass of sensation arising from a healthy meal, and lasting a certain time after the meal is finished, at which stage the operation of digestion in the stomach is the sole cause of what we feel, we may safely pronounce it to be an agreeable state of a high order. It has in a high degree the characteristic of massiveness, or amount, being a rich, luxuriant, satisfying sensation. If we were to assign the precise and specific quality assumed by it after the first edge of appetite is over, we should compare it to the sensation of genial warmth, which it appears very closely to resemble, a feeling still more enhanced by the addition of alcoholic stimulants to the food. There is manifestly a great similarity of effect on the nervous system by the three very different actions-of warmth, the digestion of food, and alcohol. Such is the character common to all kinds of healthy nourishment; but there is the greatest possible difference in the qualities of food as regards stomach relish; from turtle to stale oat-cakes, or a piece of black bread, what a mighty interval! We cannot pretend to assign the difference of digestive action that corresponds to such unequal degrees of sensation. To the richer kinds of food belong a feeling intense and keen as well as voluminous, warm, and engrossing. The magnitude of the sensation is attested by its power to submerge a great many irritations, and make itself for the time the ruling element of the consciousness. This power

belongs only to the more massive kinds of sensation, such as healthy exercise and repose, nervous elation, or the intoxication of warmth.

The Expression of this state is one of complacent satisfaction without much vehemence. In taking food, the movements are absorbed in the act, and in sympathy with the parts concerned; afterwards there supervenes a passive tone and disposition.

The energy of Volition generated corresponds to the relish and to the stage of the operation. At first the stimulus to action is intense and even furious. Appetite is only inflamed by partial gratification; and until such time as the stage of fulness draws near, the pleasure only shows itself in supplying impulse to continue it. Eating is among the most characteristic examples of the general law of Feeling-prompted Action that we can produce, being not only for the avoidance of pain, but also for the glutting of a pleasurable sensation. There is thus in a single round of digestive feeling a volitional commencement and a serene termination, the one graduating into the other.

To complete the delineation of this mode of consciousness, we may notice the peculiarity of it as related to the Intellect. In doing this, however, we have only to repeat what has been said on most of the feelings hitherto discussed, that there is comparatively little permanence in idea when the state of the organs is such as to forbid the reality. But this statement we must also qualify with the remark made above on heat, that the reality is one that can never be long absent. As a general rule, it is true of digestive and all other organic sensations, that they are exceedingly powerful when present, and exceedingly little realized when absent. They are very unlike sights and sounds, loves and hatreds, and other states that the intellect can retain in the ideal form; to imagine with effect the relish of a feast when under nausea passes the power of the most vigorous mind.

The sensation connected with the lower extremity of the canal is chiefly of the nature of a feeling of relief.

Another important healthy sensation of the alimentary

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canal is Hunger, the state preceding in order the one just described. The cause and seat of hunger are doubtless in the stomach, but on what particular condition of the stomach is yet uncertain. The feeling itself is of the uneasy painful class, with a degree of massiveness and engrossment corresponding to stomachic feelings in general. It may have all degrees of intensity, but assuming some average condition to start from, we may fairly speak of it as a sensation both powerful and keen. We can distinguish it from the sense of lassitude and faintness arising from want of nourishment to the tissues, a sense that may often be mixed up with it. Hunger, like other painful feelings, provokes to action for its appeasement, the strength of the impulse being the measure of its absolute force in the region of volition. Not being so acute or intense as a cut, a cramp, or a burn, it does not stimulate an instant and violent proceeding; but the influence on the entire consciousness of the individual is great and commanding, and the voluntary effort thence arising is of the most resolute kind. To satisfy hunger and impart stomachic relish, is one of the constant aims of human activity.

17. These are the chief alimentary feelings of the healthy kind. Among those caused by derangement, we can only select some of the most conspicuous and characteristic instances. The feeling of Nausea and Disgust is an effect indicating some great disturbance in the usual course of digestive operations. This state is associated with the act of vomiting, an act that may take place, 1. from the introduction of certain substances into the stomach, some of which, as bile, mustard, common salt, not becoming absorbed, must act simply by the impression they make on the mucous membrane; 2. By the introduction of emetics, as Tartar emetic, into the blood, or by the presence of certain morbid poisons in that fluid; 3. By mental emotion, as that excited by the sight of a disgusting object; 4. By irritation at the base of the brain.-TODD and BOWMAN, ii. p. 214. To these must be added sea-sickness. The act of vomiting is the result of a reflex stimulus directed towards the muscles that compress the abdomen in the act of expiration of the breath. These

muscles violently contracting while the exit of the air from the lungs is shut up, squeeze the contents of the stomach upwards towards the mouth. The sensation of vomiting is in most cases horrible in the extreme. It proves by a strong instance the power of stomachic influences on the nervous system. The sensation is one sui generis-no other feeling can at all compare with it. There are many forms of unendurable pain, but this has a virulence of its own, being both great in amount and intense in degree. Its connexion with the stomach gives it the peculiarity of destroying the appetite and relish for food, and of subverting nutrition at the fountain head. It manifestly extends its influence to the nervous system, and makes the nervous tissue itself the seat of intense depressing sensation. The activity of the body is for the time destroyed, the muscular system being utterly relaxed. There is a strong revulsive stimulus operating within an exhausted frame; a fact that, whenever it occurs, must needs exaggerate the misery of the sufferer.

The feelings of nausea and disgust, and the objects causing them, are expressed in our language by a variety of strong terms. The 'disagreeable' is originally what revolts the stomach, extended in its application to other forms of the unpleasing. Disgust' is the extreme opposite of relish. The fact that these words are among the strongest that the language affords to express dislike or aversion, proves how deep and intense is the feeling that they primarily refer to.

Besides the objects that produce disgust by actual contact with the alimentary canal, there are substances whose appearance to the eye is disgusting. Certain gases also affect the smell in the same way. Disgusting sights are mostly the result of association; but some nauseous smells act from the very beginning. The arrangements of human life, particularly address themselves to our protection against disgusts; and singularly enough, the chief things to be avoided are the products of living bodies themselves. This is the foremost aim of the operations of cleansing and the removal of refuse. The influences that stimulate a healthy digestion and relish are

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contrasted with the opposite by the term 'fresh,' which we spoke of already as a quality of respiration, but which has still more emphasis as opposed to the causes of disgust. The power of resisting nauseating influences is an indication of great stomachic vigour in the right direction.

There are many things entering into the ugly or opposed to the beautiful; but nothing contrasts with beauty so entirely, or annihilates it so effectually, as a disgust.

to us.

18. The foregoing cases are intended to include the most prominent of our habitual and ordinary experiences in relation to the alimentary processes. With regard to the feelings arising from disease in the various organs of digestion, these are so many forms and varieties of pain. If we were to go systematically through the entire series of organs enumerated above, we should have to commence with mastication, and describe the pains and agonies which the teeth render familiar The pain of toothache, its peculiar intensity and virulence, would appear to have some relation to the proximity of the parts to the nerve centres; any irritation about the face or head seems, so far as I can judge, to carry a greater amount of excitement to the brain than a similar irritation in more distant parts would give birth to. Distemper of the salivary glands yields a sensibility, not of the acute kind, but annoying, and difficult to bear, like disordered secretions in general. The pains and disorders of the early stages of digestion, that is in the stomach where the sensitiveness is greatest, are very numerous, and are sometimes acute and oftener not so. In proportion to the genial influence of a healthy digestion upon the general mass of sensibility, is the malign influence of an unhealthy digestive action. It is in extreme cases altogether overpowering, and renders futile almost every attempt to establish a pleasurable tone by other causes. The nervous connexion between the brain and the stomach is extremely intimate and powerful; and shows itself in many aspects. Not only is there a keen sensibility to stomachic states, but also a strong returning influence from the brain upon the digestive secretions in the way of supplementing their force,