That the lower animals are endowed with this muscular sense cannot be doubted. It enables the tiger to spring with accuracy upon his prey, the cat upon the mouse, the greyhound in pursuit of the hare when to make the fatal snap, and the horse to leap the fence, which his eye tells him is within his power; it teaches the loris to creep upon its victim, as slowly but as surely as the hand on the clock-face traverses the dial-plate, and attains the given number; it is immediately connected with instinct, and man, when he steps aside to avoid a threatened stroke, or raises his arm to parry a blow, puts the muscular sense into exercise. The muscular sense is, to use a homely expression, an every-day working sense; touch and sight are its prime supporters, and to these in turn it lends its aid. Nevertheless, to a certain degree it is independent of them; the infant seeks the breast as it were by an instinctive impulse, or applies the coral to its mouth; and in the dark as well as in the light, we transmit our food directly and precisely to the organs of mastication and deglutition, without thinking upon the manner in which the varied actions are performed, or even transiently noting them. We _will_ to perform an act within our power of achievement, and by the complicated action of muscles, nerves, vessels, and bones, we accomplish our object, at the same time, perchance, we know not the origin and insertion of a single muscle, the direction of a single nerve, the course of a single artery. The muscular sense is, in fact, in perpetual exercise; it is intimately connected with self-consciousness, for we feel that we corporeally exist, that other bodies exist around us, that they resist us, that they lead us to calculate our own powers, nor will all the arguments of the school of Berkeley convince us that we exist only in idea. When Dr. Johnson stamped upon the ground to disprove Berkeley's idea, he was right.