So, again, if the child is at fault, he does not think of the meaning of the sentence, and of what is wanted to complete it; but "tries back" over the preceding words, that their sound may suggest that of the word he desiderates. So there are older persons, with whom the pictured remembrance of the words and phrases is more suggestive; as in a case to be presently cited.—Now, in these instances, it is a familiar fact that what is thus learned but once, however perfectly, soon "goes out of the head," being only fixed there by continual repetition; and, as the Memory we are now considering is rather Sensorial than Ideational, this fact is confirmatory of the doctrine that seems probable on other grounds, of the superior (if not the exclusive) persistence of the latter. We seem distinctly able to trace the action of the recording process in this elementary form of Memory, in the help given in the "learning by heart" of a task, by repeating it the last thing at night; for every school-boy, who has to commit to memory fifty lines of Virgil, knows very well that, if he can "say them to himself," even slowly and bunglingly, just before going to sleep, he will be able to recite them much more fluently in the morning. The Physiologist sees here an obvious indication that the recording process has gone on without interruption by new impressions on the Sensorium, so that there has been time for the fixation of the last by Nutritive change. We have, indeed, a remarkable converse phenomenon, in the rapid fading away of a Dream, which, at the moment of waking, we can reproduce with extraordinary vividness; for the "trace" left by its details is soon obliterated by the new and stronger impressions made on our waking Consciousness, so that, a few hours afterward, we are often unable to revive more than the general outline of the Dream—and perhaps not even that, unless we have told it to another when it was fresh in our minds, of which act a "trace" would be left.
There are two classes of persons who are professionally called upon for great temporary exercises of Memory, viz., Dramatic Performers and Barristers. An actor, when about to perform a new "part," not only, commits it to memory, but "studies" it, so as to make it part of himself; and all really great actors identify themselves for the time with the characters they are performing. When a "part" has once been thoroughly mastered, the performer is usually able to go through it, even after a long interval, with very little previous preparation. But an actor is sometimes called upon to take a new "part" at very short notice; he then simply "learns it by heart," and speedily forgets it. A case of this kind is cited by Dr. Abercrombie, as having been the experience of a distinguished actor, on being called on to prepare himself in a long and difficult part, at a few hours' notice, in consequence of the illness of another performer. He acquired it in a very short time, and went through it with perfect accuracy; but immediately after the performance forgot it to such a degree that, although he performed the character for several days in succession, he was obliged
