_Touch_, next to sight, is the most important of the senses. The whole skin possesses this sense, but in some parts far more than others, the finger-ends being the most perfectly endowed with it; and in the lower animals the parts which are used as prehensile organs, are in them the most acutely sensitive to touch, as the end of the proboscis in the Elephant, and the lips of most other quadrupeds. In the Feline tribe, the smellers or hairs from the side of the face, appear to be true organs of touch, and enable them to feel their way in the dark. By the sense of touch we are informed of the amount of resistance of matter (and consequently its weight), of hardness, smoothness, roughness, and other qualities of surface, and by the amount of extension of the hand to reach them of their distance from us, and also of the form and size of things. [Illustration: FIG. 87.--TIGER'S HEAD AND ELEPHANT'S TRUNK.] The human hand is the most perfect organ of prehension possessed by any animal, for although Monkeys have hands, yet these are so imperfect as to serve chiefly for clinging to, and climbing amongst the branches, they cannot take any small substance between the thumb and finger, while the human hand, besides enabling its possessor to grasp firmly with all the fingers and thumb, each can individually be approximated to the thumb so as to hold the very smallest substance, and as Man is so constituted that he can stand firmly on his feet, his hands can be solely appropriated to the acts of prehension. It has been said that Man owes much of his superiority to the lower animals, to the possession of hands which can take, examine, and compare everything within his reach; but it seems more probable that these hands have been given him because he, only, has the faculties of examining and comparing. The Lion and Tiger would be no better off, had they Man's hands instead of their feet with claws--probably much worse. [Illustration: FIG. 88.--HUMAN HAND.] [Illustration: FIG. 89.--MONKEY'S HAND.] Animals do not feed upon unorganised matter, as do vegetables, but merely appropriate to their own use those organic principles which are ready formed in the vegetable or animal, such as albumen, fibrine, starch, gum, sugar, &c., and assimilate them into their substance. [Illustration: FIG. 90.--HUMAN STOMACH.] [Illustration: FIG. 91.--LUNGS, HEART, AND LARGE VESSELS. 1 and 2, Right and left Lungs; 3, Heart; 4, Aorta; 5, Trachea.]