The muscles of an infant are soft and not capable of great effort. Not till after the sixth month are they felt firm and resisting. To develop them the clothing should be loose, and the child, in a nude state, should at times be allowed free play of them. To swathe the feet and limbs in bandages ato make the child straight° is hurtful.
The abdomen and chest (in its lower por tion) are prominent, due to the very large liver, the small pelvis and the distention of the stomach by food, and to large size of the heart and lungs. All of these organs must have free movement, in order to carry on their important functions. Tight bandaging of chest or abdomen hampers movement and compresses important blood vessels. The size and weight of the heart of the new-born explains the rapid growth of the body and those organs in most direct com munication with the heart, especially the brain. The small size and the vertical position of the stomach account for the ease with which infants throw up their food when the stomach is dis tended. Repeated acts of vomiting are inju rious. The practice of jolting babies tends to produce vomiting. Each child must be studied by itself as to its powers of digestion, and what is the proper food for each. The substitution of artificial feeding for maternal nursing and the indiscriminate use of baby foods are responsible for much sickness and many deaths. But nat ural feeding is not always possible, owing to the dictates of fashion or the poor health of mother or child.
The nervous system of infants is very ex citable, especially toward the end of the first year, and is out of proportion with the slow development of the inhibitory centres. Convul sions and spasmodic affections are therefore readily produced by various causes, such as un digested food, eruptive fevers, impure air, fright or excessive heat. Most of the move ments and actions of early infancy are reflex, such as stretching, crowing and sighing, for example. About the fourth month evidences of will power appear and gradually increase. Good habits, as to regular times for feeding, sleep, etc., can often he inculcated at this early age, or even before, to the advantage of both mother and child. The brain is relatively large at birth and grows rapidly tip to the seventh year, and after that time more slowly.
During this formative period care should be observed not to excite the brain unduly, else nervous disorders may result. Repeatedly urging a young child to ashow off° is, to say the least, very unwise.
The senses of taste and smell seem to be partially developed at birth. After the third month the quick closure of the eyes on the approach of an object seems to indicate the es tablishment of true vision. A very bright light may be appreciated by the second or third day, or may be followed by the eyes, if moved slowly, after the sixth week. It is usually weeks before there are associated movements and convergence of the eyes. The eyes of the new-born fre quently move independently of each other, pro ducing °squint,* but squinting in the course of a severe disease 'is a had sign. As to colors, yellow, red, pure white, gray and black, in the order named, are said to be the first recognized, gradually after the sixth month.
All children are born deaf, but may notice sharp sounds six hours after birth, though'usu ally not until a number of days. Toward the end of the first year the infant begins to imitate vocal sounds in its attempt to speak.
The circulation of blood is very rapid; the blood vessels are large and thin. Congestions, inflammations and haemorrhages, therefore, are quite common. The pulse is irritable and slight causes disturb its rate and sometimes its regularity. The rate in the new-born is 130 140, during the first year 105-150 per minute, during the second 110-120, then gradually di minishes until at the fifth year it is about 90; from the 7th to the 14th year 80-90, and after ward 70-80. The respirations of the new-born are from 30 to 50 per minute, and at the end of the first year from 25 to 35. The breathing of healthy children is noiseless and through the nose. The habit of mouth breathing, usually caused by enlarged tonsils and by ade noid growths, is productive of deafness, change in facial expression and distortion of the chest (pigeon breast). The relatively small size of the pharynx, larynx and trachea frequently cause throat affections to be serious ailments in infants.