tween his inherited cerebral capacity and the actual demand for mental activity shall be restored.
We have now only time left us to review briefly two or three of the many peculiarities of savage life which stimulate increasing mental activity and its physical manifestation in convolutional development, and which peculiarities do not to the same extent, if at all, affect civilized men, and especially the routine laborers among them. To do this exhaustively would require a volume, and we can therefore only glance at the matter in the most cursory manner.
It is an open question as to the extent that the use to which learning is to be put constitutes a factor in determining the value of the mental development received in acquiring such learning. To whichever school of thought one may incline, it can hardly be denied by either side that in the acquisition of the same knowledge by two persons, the one for one purpose and the other for an entirely different but equally important object, the strengthening and developing effect, other things being equal, would be the same. Now the common hunting savage of the neolithic age takes up one branch of the study of natural history and pursues it until he is able to teach an Agassiz, an Audubon, or a Darwin. Not one of these learned men knew, after a life of study and observation, as much about this one thing, the habits of the wild beasts, birds, and fishes, as does the average savage hunter. To him such knowledge means food and life, and the lack of it hunger and starvation. He must know their color, size, and movements; when, where, and how they get their food and water; where and how they make their nests or lairs or homes; when they rest and when they go forth, and where; all their cries and sounds, and the meaning of them; and he must be able to imitate them so exactly that they shall think these sounds made by one of their own kind; he must know when and where they are moved about by winter and summer, by drought and flood; when and where they breed their young, and in each case whether the young are protected by hiding, defense, or flight. He must know what animals have leaders or sentinels, and how to distinguish them, and how to interpret their sounds of alarm, and distinguish them from the sounds of safety, and he must be able to perfectly produce both; he must know their strength, alertness, and acuteness of sense, speed, and endurance as related to the species and to the age and sex of the individual; he must be familiar with their dispositions, their courage, cunning, intelligence, and timidity, and be able to determine in advance what they would probably do under all conceivable conditions. Then it is not less necessary that he should know all the relations of each species to each and all of the others. To acquire this
