genious enough to swing sticks, and the orang will break off branches and fling them at his tormentors or hurl the thick husks of the durian fruit. Nevertheless, striking and throwing are exceptional even with the semi-terrestrial apes, or at most only occasional exercises with such as have sometimes to defend themselves upon the ground. But for man the conditions were reversed. After the human prototype had parted company with his arboreal fellows to become a land-dwelling creature, swinging and climbing were no longer essential to his success. Henceforth he had to win a place for himself on the ground, and lacking natural means of attack and defense, in the course of his contest with the carnivora, he was compelled to exercise ingenuity in the choice of artificial implements and develop his incipient capacity to strike and throw. It is not so strange, therefore, as it at first sight appeared, that in adapting the human prototype to his earthly environment selection should have simply set him upright on his feet and accorded him the free use of his arms and hands; for, with his inherited mental endowment, these slight structural modifications were just such as were necessary to make him a weapon-wielding animal and so set him above his enemies.
But besides becoming psychically and physically fitted for striking and throwing, man's faculties had also to be trained before he could acquire proficiency in the art of weapon-wielding. To deal a straight blow with a club, or hit a distant mark with a missile, it is necessary to take accurate aim; and this involves the development of a good eye. Heredity favored the human prototype in this respect, for his ape-like ancestors had for centuries been accustomed to rely upon their sense of sight in their search for subsistence. In developing his incipient capacity to strike and throw, the pliocene precursor had, therefore, simply to turn his inherited acquisitive sense to the additional service of distance-determining and range-finding. Long practice and hard training must, nevertheless, have been necessary before primeval man acquired the knack of aiming accurately. The semi-terrestrial apes, whose instincts are still set and whose organs are primarily adapted to swinging and climbing, have never acquired any special facility in this direction. With the exception, indeed, of the land-dwelling, tree-climbing baboon, who is apparently able to hurl branches and hard clods with considerable dexterity, they all exhibit a ludicrous lack of skill in striking and throwing. On the other hand, by dint of observation and imitation, the small boy of our day soon learns to take accurate aim, and savages without exception show surprising skill in this direction. Considering the necessity of the case, and judging from the fact of human survival, it is extremely probable, therefore, that in the course of his contest with the carnivora the prototype acquired the knack of aiming accurately and eventually became an adept in the art of weapon-wielding.