and unconscious certainty after a great amount of practice; but the docility of the lower limbs is far inferior to the hands, while I should be disposed to reckon these second to the

voice.

The difficulty of forming a perfect association of mere movements, and the dependence of most of the mechanical trains upon the sense of the effect produced are curiously illustrated in the cases of paralysed sensibility. Thus there is an often quoted case of a woman who could not hold a baby in her arms except by keeping her eyes fixed upon it. She had no sense of weight in the arms, and the sustained tension of the muscles was not sufficiently associated with the taking up of the child, by the muscular link alone. The sight of the eye was able to supply the want of arm sensibility, but both could not be dispensed with.

It is the linking together of unconscious movements that makes the human framework purely automatic and mechanical; constituting a series of actions exactly parallel to the instinctive arrangements so often alluded to. To get rid of consciousness as an essential part of any piece of execution is to eliminate the foremost characteristic of mind; this is not done so long as the sense of effect is necessary to keep up

the action.

Although very few of the cases of mechanical acquirement in general can belong to the class we are now considering, there are important distinctions of character founded on the facility of acquiring trains of movement so as to keep them up with the least possible help from the guiding sensations and ideas. The trains of action thus acquired cost the smallest amount of mental fatigue in the performance; they may, moreover, go on with the mind employed upon other things. In the execution of work these are valuable characteristics; on the other hand, inasmuch as all such actions cease to occupy the mind, they leave it a prey to ennui if other occupation is not provided. Thus in devotional ceremonies that have reached this point of adhesion, there is apt to be a loss of interest.

4. The inward process whereby movements repeated in the same succession acquire coherence and bring on one another

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in the proper order is one of the hidden qualities of mind. We may describe the effect, and specify some of the important physical conditions that control it, but we can go no further. It is a fundamental property of the mental and nervous system, and is unique in its kind, there being nowhere any other instance of it known to us, no other substance but nerve possessing the like property.

The actions thus associated are voluntary actions; they are stimulated from the cerebral centre, and it is within the cerebral hemispheres that the adhesion takes place. A stream of conscious nervous energy, no matter how stimulated, causes a muscular contraction, a second stream plays upon another muscle; and the fact that these currents flow together through the brain is sufficient to make a partial fusion of the two, which in time becomes a total fusion, so that one cannot be commenced without the other commencing also. The current that directs the lifted arm to the mouth is part of a complex stream that opens the jaw; the current that gives position in the fingers of a flute-player is associated with another that fixes the lips, and a third that compresses the chest with a measured force. In virtue of passing through the common centre of the nervous system together, the many different coinciding streams become after due continuance an aggregated unity, broken up only by some more powerful alliance.

In the same manner may we express what happens in successions of acts. If the brain stimulates a given movement, such as the utterance of an articulate syllable, and if after that a second syllable is pronounced, there is a continuity established between the two, a sort of highway made, and a bent given to pass from the one act to the other; in the course of time and repetition the connexion is fully knit, and the transition becomes mechanical or automatic. The acts must be mental or conscious acts, lying in the course of the common stream of mental activity: which stream is turned first upon the one, passes next to the other, thereby, as the effect shows, establishing a tendency towards the same direction ever afterwards.

It may be very fairly assumed that this is a process of growth like the natural development of the nerves and muscles themselves. This view is ably expressed by Dr. Carpenter. Whether the growth lies in forming new cells, or in modifying the internal conductibility of the nerve fibres and vesicles, we are unable to say; there is no reason why both effects should not take place. But the circumstances connected with the process of education strongly favour the above comparison. We find, for example, that new acquirements are easiest and most rapid during early life, the time of most vigorous growth of the body generally. We find also that rest and nutrition are as much needed for educating the organs as for keeping up the bodily health. There is, moreover, a bound fixed to the rate of acquirements, and no amount of practice can enable us to get over it. The plastic or hardening operation takes a certaiu interval of time, and although the current be never so much sustained, by keeping at a thing, the rate of acquisition is not increased in the same degree.

In successions of movement, the completed act of one movement is the link that sets on the next. But it is in vain, at the present point of our knowledge, to enquire minutely into the steps of this subtle sequence.

5. The conditions that regulate the pace of acquisition, or the cohesion of set trains of movement have a high practical, as well as a theoretical interest. Some of these conditions are common to all kinds of acquisitions, while others are limited in their application. Those that relate to movement are the following:

(1.) The command already acquired over the organs. This throws us back upon previous acquisitions, and upon deep peculiarities of character, that need not at present be discussed. But it is well known that some persons, in commencing manipulation, have a much better command of their movements than others; that is, they get more readily at a posture or movement pointed out to their imitation. Previous to the plastic fusion must come the proper performance of the

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separate acts that have to be made coherent. It is necessary to sound each note well before singing an air. So with all the minute shades of movement entering into a delicate operation requiring flexibility of organ, and the power of graduating the stress exerted according to the nicest shades. of difference.

(2.) There is a natural force of adhesiveness, specific to each constitution, and distinguishing one individual from another. This property, like almost every other assignable property of human nature, I consider to be very unequally distributed. We can get at an estimate of such primitive differences only after allowing for all the differences in the other circumstances that do not depend upon character. In the case now before us-the acquisition of movements— the difference is apparent in the very unequal facility shown by boys in the same school, or recruits drilled together, in mastering their movements. The power of acquiring trains of movements easily is the prime requisite in the education of the army, and in all mechanical arts, both as enabling the individual to attain a high pitch of dexterity and effectiveness, and as dispensing with the sense of effort and consciousness in general, in other words, with mental exertion and fatigue.

(3.) The main circumstance, next to original endowment, is Repetition or Continuance. In proportion to the repetition is the rate of cohesion, regard being had to the necessity of reposing the organs. It is possible to make up for all other defects by repetition. We term that constitution most adhesive by nature, that needs the fewest repetitions to become perfect.

(4) The amount of nervous energy concentrated in the act is a vital circumstance in determining the rapidity of fixing it. This is a variable thing in the same individual.

In the first place it depends on the nervous vigour of the moment, as contrasted with feebleness, exhaustion, or lassitude. The voluntary energy that sustains an action rises and falls with the condition of the body; hence the freshness of the

morning and early part of the day determines the best time for drill. So also good health is a condition of education in general.

But the concentration of nervous energy may be prevented by the diversion of the mind into some other channel, or the expenditure of the inward power on other efforts. Distraction or pre-occupation effectually checks our progress in any attempt; the motions may be made, but the coherence is feeble. Thus a child may go through the repetition of its lessons, but while the mind is diverted elsewhere, there is no progress in fixing them. Intense pleasure or pain, or emotion of any kind, excited by causes foreign to the work in hand, use up the mental expenditure, the currents of circulation and nutrition, that ought to go to the plastic process.

The nervous energy may be called forth by mere volition. A strong determination to learn a movement is very much. in our favour. Some people cannot determine anything vigorously; in others the energy wrapt up in any act of volition is very high.

This voluntary effort may be stimulated by emotion or excitement. Terror is a very common stimulus applied to a learner. The objection to it is the cost, both in suffering and nervous waste. The best of all stimulants is a strong liking for the thing in hand.

It is one of the peculiarities of what is called the nervous temperament, or a nervous system naturally prone to vigorous exertion (just as some constitutions are strong in muscle, and others in digestion), to expend itself copiously in all its efforts, voluntary or emotional. This is necessarily favourable to acquisitions, as to every other mental manifestation.

(5.) In mechanical acquirements we must not omit bodily strength as a favouring circumstance. The power of continuing the exercise without fatigue, and the great determination of nutritive matter to the muscle at least, which is implied in a strong bodily frame, cannot but be favourable to the fixing of movements and the forming of habits. Hence strong men may be expected to acquire athletic and handicraft accomplishments more easily than others. But although