Use of the right and left hands.—My observations of R.'s use of the right and left hands began in his third month, and were directed to answer the one question, which hand does the child use more? The record is not as full of definite, detailed statement as one wishes, the usual form of the note being, "right hand preferred," "uses the left hand more at this time," "holds ball in right hand," and so on. I do not mean, however, to cast doubt upon the accuracy of the "mere impressions," as one may call them which the notes contain. They were based always upon careful observation of the child's hand-movements during half-hour or longer periods; and on several occasions the number of times each hand was used in picking up, reaching, feeling, pulling, throwing was counted, and the result entered in the notes. But this method was not followed uniformly, hence the lack of full, detailed statement.
Third month.—No preference for either hand was noticeable.
Fourth and fifth months.—In these months the right hand was used more frequently.
Sixth to eleventh months inclusive.—No noticeable preference for either hand.
Twelfth to the close of the thirty-sixth month.—A slight preference for the left hand began to appear early in the twelfth month, and it increased so rapidly that by the time the child rounded out his first year he
