but repetition of movements is extremely likely to occur. Thus, three feints are made and then a blow is struck, and, this continually occurring, the adversary soon finds out his opponent's method of procedure, and acts accordingly. If a stable motor memory have been formed, great difficulty will be found in striking a blow at the first, second, or third movement, or in missing the fourth without making one. So that it is necessary to carefully consider the nature of the motor memory in relation to a movement to be performed, and to avoid acquiring any habit of this kind.

RULE XXI.—When an erroneous special motor memory has been established, no attempt should be made to unlearn it, as it is called, by repetition of the correct movement; but this should be learnt with the aid of some slight premonitory trick, as a separate and distinct action.

When some habit has become established by the motor memory, as some erratic movement in dancing, it is often extremely difficult to break, the old movement being performed directly the attention is allowed to wander. It is best in these cases to adopt such a modification as will enable the student to adhere to the correct movement, the essential difference being borne in mind. Each time the corrected movement is performed, some other slight action should be executed as well-something which is quite trivial and unnoticeable, as bending up the forefinger into the palm, slightly biting the inside of the lip, etc. This will soon become strongly associated with the correct movement, and the two will be carried out together; the premonitory trick being performed just before the corrected movement, a

special motor memory will be accordingly developed, and the corrected movement executed with ease. But, as I have shown when speaking of the direct combination of the memories, when a sensory memory impression is continually followed by the execution of a certain movement, the one will soon naturally follow the other, at last, without even cognizance of the mind. It will be seen, from this, that the establishment of some special memory impression, to be continually followed by the requisite movement, will be quite sufficient; thus, let the student continually excite some impression, as a number or particular idea, just before the execution of the movement, until it has become properly established.

RULE XXII.—When a movement has to be performed, no idea of negation of some other movement should be

allowed to enter the mind.

The advantage of attending to this rule is very great, and the reason for it is shown in the direct combination of memories which occurs when any movement is being acquired. Now, if a sensory impression, which is usually followed by some particular movement, be revived, that movement is very likely to occur, especially if the person be using his muscles at the time. The seat of judgment, reflection, and the other conscious processes of the mind, is in the cerebral hemispheres; the motor memory, except through a sensory impression conveyed to the mind, affords no information of its workings, and so the most curious. blunders are made. Thus a man writes a letter, having in his mind the necessity of not making some particular remark, and finds, to his astonishment, on

reading the letter, that he has made the remark, that he has used the affirmative when he intended to use a negative. So instead of allowing an idea of 'I must not do this' to be in the mind, an idea of 'I must do that' should be substituted. This should especially be borne in mind when writing an examination paper. I have heard of some very curious and outrageous blunders, and feel sure that many of them must have occurred in the above way, as there is, usually, not time to read over what has been written; and it is impossible for an examiner to say, in many instances, whether the mistake be due to ignorance or a slip of the pen.

In the same way, if, when a movement has to be corrected, the idea of 'I must not make the old mistake' enter the mind, it is extremely likely the mistake will be made.