learned, say, in four half-hours put upon it at different intervals, than we should by spending the whole two hours upon it at one time. Another condition favourable to recall is the recency of the original experience. Anything is more easily recalled, the more recently it has been learned. The physiological cause for this seems to be that the nervous co-ordinations being recent, they are much more likely to re-establish themselves, not having yet been effaced or weakened through the lapse of time. =B. Mental Conditions.=--It must be noted, however, that although there is evidently the above neural concomitant of recall, yet it is not the nervous system, but the mind, that actually recalls and remembers. The real condition of recall, therefore, is mental, and depends largely upon the number of associations formed between the ideas themselves in the original presentation. According to the law of association, different ideas arise in the mind in virtue of certain connections existing between the ideas themselves. It would be quite foreign to our present purpose to examine the theories held among philosophic psychologists regarding the principle of the association of ideas. It is evident, however, that ideas often come to our minds in consequence of the presence in consciousness of a prior idea. When we see the name "Queenston Heights," it suggests to us Sir Isaac Brock; when we see a certain house, it calls to mind the pleasant evening spent there; and when we hear the strains of solemn music, it brings to mind the memories of the dead. Equally evident is the fact that anything experienced in isolation is much harder to remember than one experienced in such a way that it may enter into a larger train of ideas. If, for instance, any one is told to call up in half an hour telephone 3827, it is more than likely that the number will be forgotten, if the person goes on with other work and depends only on the mere impression to recall the number at the proper time. This would be the case also in spite of the most vivid presentation of the number by the one giving the order or the repetition of it by the person himself. If, however, the person says, even in a casual way, "Call up 1867," and the person addressed associates the number with the Confederation of the Dominion, there is practically no possibility of the number going out of his mind. An important mental condition for recall, therefore, is that ideas should be learned in as large associations, or groups, as possible. It is for the above reason that the logical and orderly presentation of the topics in any subject and their thorough understanding by the pupil give more complete control over the subject-matter. When each lesson is taught as a disconnected item of knowledge, there seems nothing to which the ideas are anchored, and recall is relatively difficult. When, on the other hand, points of connection are established between succeeding lessons,