Page:Popular Science Monthly Volume 55.djvu/537

Rh touch, and the other senses, show that there is lessened ability in conditions of fatigue; and this is accounted for probably by the waning power of attention. The mind can be held to one thing, excluding irrelevant matters. This phenomenon is further illustrated in the following simple experiment: The pupils in a large graded school in Buffalo, N. Y., were required upon three successive days, at half past nine o'clock and again at half past eleven in the morning, to trisect a line three inches long. The results, calculated for one hundred and fifty children, show that on the average they were several millimetres nearer correct in the morning trisections than in those just before the midday recess. It seems that this test measured the degree of attention which pupils were able to exert at different hours during the day, and it confirmed what must in a way be known to every one—that a day's work in school reduces the energy of attention. Doubtless every instructor has remarked how much more difficult it is at half past eleven than at ten to hold the thoughts of students to the subject in hand, and if recitations in intricate studies occur late in the forenoon, progress will be slower and more errors will be made, simply because pupils are unable to attend so critically.

The significance of this latter effect of fatigue must be apparent when it is realized that attention is at the basis of all the intellectual processes. If one can not attend vitally, he can not perceive readily or accurately; he will be unable to recall fully or speedily what has formerly been thoroughly mastered; and, most serious of all, he can not so well compare objects or ideas to discover their relationships—that is, he is not so ready or accurate in reason. In fatigue, then, one really becomes stupid. Suppose a fatigued pupil in school working over his spelling lesson, for instance; he will be liable to make errors both in copying from the board and in reproducing what he already knows. In recitations in history, memory will be halting; what has apparently been made secure some time before now seems to be out of reach. In those studies requiring reflection, as arithmetic, grammar, geography, and the like, the reasoner will be unable to hold his thoughts continuously to the matters under consideration, and so will be unable to detect relationships between them readily and accurately. When one considers, in view of what is here set forth, that many persons, adults as well as students, are for one cause or another in a constant