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volition established in the animal system. This is the first case of action for an end, or under the prompting and guidance of a feeling, that the newly-born infant is capable of.

Besides the natural craving for the elements of nutrition required by the tissues, we may acquire artificial cravings by the habitual use of certain forms of food, and certain accompaniments, as peppers, flavours, &c. Thus we have the alcoholic craving, the craving for animal food, for tea, coffee, snuff, tobacco, &c.

5. The Appetite that brings the Sexes together is founded on peculiar secretions which periodically accumulate within the system, producing a feeling of oppression until they are either discharged or absorbed; there being a certain intense pleasure in discharging them for the ends of reproduction. If we were to place these feelings among Sensations, they would either form a class apart, or they would fall under the first class above described, namely, the Sensations of Organic Life. If the subject were open to full discussion, like the other feelings of human nature, it might be best to treat them as an organic sensibility giving birth to a special Emotion. We have in this case, as in Hunger, both Appetite and Desire; but we have also, what does not occur to a like degree in hunger, a many-sided susceptibility to inflammation,—through all the senses, through the trains of thought, and through various emotions.

6. The accustomed Routine of life leads to a craving almost of the nature of Appetite. As the time comes round for each stated occupation, there is a tendency or bent to proceed with that occupation, and an uneasiness at being restrained. So, our appetites properly so called may have their times of recurrence determined by our customary periods of gratifying them.

7. All the appetites are liable to be diseased or perverted, and to give false indications as to what the system needs. They are likewise liable to artificial and unseasonable inflammation, through the presence of the things that stimulate and gratify them. In the lower animals, it is assumed, I know



not with what truth, that appetite rarely errs; in humanity, error is extremely common. We are apt to crave for warmth when coolness would be more wholesome; we crave for food and drink, far beyond the limits of sufficiency; we indulge in the excitement of action when we ought to cultivate rest, or luxuriate in repose to the point of debility. So doubtful is the appetite for sleep, that there is still a dispute as to how much the system requires. Perhaps the complicacy and the conflicting impulses of the human frame, are the cause of all this uncertainty and mistake, rendering it necessary for us to resort to experience and science, and to a higher volition than appetite, for the guidance of our daily life.

1. IN



N the foregoing chapters have been enumerated all the primary modes of consciousness; we have now to consider in full the original provision in the human system, for ACTION. The name 'Instinct' is especially reserved for what is primitive or primordial on the active side.

More expressly, INSTINCT is defined as the untaught ability to perform actions of all kinds, and more especially such as are necessary or useful to the animal. In it a living being possesses, at the moment of birth, powers of acting of the same nature as those subsequently conferred by experience and education. When a newly dropped calf stands up, walks, and sucks the udder of the cow, we call the actions instinctive.

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2. In all the three regions of mind,-Feeling, Volition, and Intellect, there are certain primitive and fundamental arrangements, which education or acquisition proceeds upon. A full account of all our instinctive endowments may be included under the following heads.

1. The Reflex Actions.-These are actions withdrawn from the sphere of mind, and yet having analogies, as well as contrasts, with proper mental actions.

II. The primitive arrangements for combined and harmonious actions.-The rhythmical acts of walking, flying, swimming, &c., are examples of these. The Will may supply the stimulus to move, but the harmonious grouping of the movements is, in many instances, provided for among the natural endowments of the system.

III. The connexions existing at the outset between Feeling and its bodily manifestations.

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IV. The instinctive germ of Volition. What we call the power of the will, has to be traced back, if possible, to some inborn or primitive stimulus, connecting together our feelings and our actions, and enabling the one to control the other. This is perhaps the most delicate inquiry that our science presents.

The primitive foundations of Intellect, I shall defer till the whole subject is entered on in the Second Part.

v. The description of the special mechanism of the Voice, will receive a place at the conclusion of this chapter, not having been included in the chapter on Movement.


3. The Reflex, Automatic, or Involuntary actions, are marked by the absence of the circumstance characterizing voluntary actions, namely, the stimulus and guidance of feeling. Many of them are essential to animal life. They all demand a nervous arrangement, consisting of incarrying and outcarrying fibres, connected by grey matter. Some are maintained by the system of sympathetic nerves and ganglia, which are the most detached from the brain or centres of consciousness; others depend on the spinal cord; a third group are related to the medulla oblongata; and some are actuated by still higher centres, as the pons varolii and the corpora quadrigemina. Occasionally the sympathetic ganglia and a portion of the cerebro-spinal masses concur to the responsive movement.

The Reflex Actions may be distributed under the following heads.

First, those concerned in the organic processes, and operated through the involuntary muscles,-being the most widely removed of all from the mental or voluntary sphere.

The rhythm of the heart is usually counted among reflex actions, but no precise stimulant can be readily assigned. The power emanates mainly from the sympathetic system of nerves, and especially from the ganglia distributed on the heart itself; the rhythm continuing for some time, even after removal from the body. The influence is thus of the nature of regulated or rhythmical spontaneity, rather than of reflected action. The

accomplished contraction of one portion of the muscular substance is the signal for commencing the contraction of another portion; and no other antecedent can be specified. The mere contact of the blood with the muscular wall of the organ is not to be considered a stimulant, such as would give rise to a reflex act. By galvanizing certain parts of the sympathetic system, in the neighbourhood of the heart, the beats are accelerated. On the other hand, by the stimulation of the vagi nerves, the action is weakened; this is in accordance with a tendency of the cerebro-spinal nerves to hold in check the influence of the sympathetic centres. It is found, however, that the complete removal of the cerebro-spinal centres has a weakening effect upon the heart's action, showing that, on the whole, some contribution to the force of its pulsations is derived from beyond the confines of the sympathetic system. So, irritation or excitement of the spinal cord of a recently decapitated animal, increases the force of the heart in common with the intestines and other viscera. While states of mental excitement, especially of the joyful kind, are accompanied with an improved tone of the circulation, depressing passions lower it; effects depending on the comparative energy of the sympathetic and the cerebro-spinal centres.

Connected with the circulation of the blood, there is also, what is called, the vaso-motor action; whereby the smaller arteries, which possess muscular fibres, are contracted or expanded, so as greatly to modify the local circulation. The contraction of these fibres, due to the influence of the sympathetic nerves, diminishes the bore of the vessels, and lessens the flow of blood to the parts; their relaxation widens the bore, and gives an increased flow, with rise of temperature and quickened action upon the nutrition of the locality. The permanent contraction, maintained in these fibres through the influence of the sympathetic centres, is one of the examples of the spontaneity of muscular energy, and is not a pure case of reflex stimulation.

Through the vaso-motor agency, the secretions and excretions are greatly affected by nervous influence; it being uncertain whether this is the sole instrumentality whereby the processes of organic life are subjected to the nervous centres.

More clearly reflex are the movements of the intestines. The whole of the intestinal canal is provided with muscular fibres,

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