Repetition is perhaps the most common device to fix anything in the memory. The school boy thinks that if he repeats his les son enough times it will stick. But he does know why or how repetition helps him to remember. It is probable that at each repetition some new association will be formed. It may be also that in the course of the repetitions the impressions may be deep ened by awakening thought. In both cases lines of suggestion are established which will help to recall the lesson. The more careful and thoughtful the repetition the more certain the memory. Parrot like repetitions help little, except as they sometimes form a habit in the organs of speech. We see this illustrated in learning the multiplication table. Children are often obliged to say the table from the beginning of the line till they reach the number they wish to remember. READY AND RETENTIVE MEMORIES. We may now see the difference between readiness and retentive ness of memory, and how they are formed. The ready memory, which seems able to call up at will its stores, depends upon the large number of associated ideas which stand ready to suggest the idea wanted. These associations are formed by many repetitions of the thought. Thus the child readily remembers his alphabet, and the man the rules of his trade, the lawyer his cases, and the engineer his formula. Language is learned largely in this way, and affords a good example of the ready memory. On the other side, the retentive memory depends upon the depth of the impression and the strength of the association. It also rests in many cases upon the logical connection between the idea and those with which it is linked. Scientific facts are mostly retained in this way. The facts are associated in classes, by the relations of resemblance, and also by the relation of cause and effect which connects them in classes and series. One other principle in memory needs to be noted. The mass of knowledge already memorized aids powerfully to gain and re member more. As in the winter sport of rolling snow balls, the handful of snow with which we begin gathers but little in its first revolutions; but as it increases in volume and weight it gathers faster and faster, till finally it takes up all it comes in con tact with. Let two men of different callings read the same news paper; each one takes and remembers the facts which concern his own business. The lawyer remembers legal news, the physician The Free Lance ' [ MARCH,