A new-born baby cannot probably do any more than distinguish light from darkness. Up to the sixth week there is an inability at coordination of the ocular muscles; after this time the eyes begin to move in an orderly manner, and they will follow a bright object moved slowly in front of them. At about the end of the second month rapid movements are perceived, as is evinced by the child's closing its eyes quickly on an object suddenly approaching it. At three months the child begins to recognize colors; the first recognized are yellow, red, pure white, gray, and black. But the faculty of distinguishing between colors is not perfected till the third year. The mother is recognized about the third month. Hearing and a sense of smell develop rapidly after birth; loud noises in its vicinity will cause a child to start during the first day after birth. By the time the child has reached three months of age it shows signs of having a mind of its own, and is capable of exercising thought. It grasps for objects, and indicates its likes and dislikes. At from eight to ten months it can utter several syllables, and at the age of one year should be able to say mama and papa; at two years it should be able to frame short sentences.
Weight of the Baby.-- By the end of the sixth month the child's weight should be double what it was at birth; that is, about fourteen pounds; at the end of the twelfth month be three times as much as at birth, or about twenty pounds.
Muscular Action.-- Muscular action in the new-born infant is entirely involuntary, there being no voluntary acts until about the end of the third month. Sucking and licking are largely instinctive. The movements of the arms and legs are impulsive acts, and occur during sleep, just as they did in the intra-uterine life. The act of raising the head, which is attempted about the fourth month in healthy children, is volitional, requiring not so much added strength of muscle as power of coordination. As volition develops the power of coordination gradually increases, and the child learns to perform voluntary or purposeful acts. Voluntary grasping is done after the fourth month. As the child learns to balance its head, it attempts to sit up. This act is not successfully accomplished until about the fortieth week; the child sits firmly alone when ten or eleven months old. Before this time it is necessary to support the head and spine of the child with the hand. By the third or fourth month the infant should be able to grasp things. The child begins to creep about the ninth month. The clothing should be so arranged as to allow entire freedom of motion.