The Period of Childhood may be said to extend from the end of the second year to puberty or youth. By the end of infancy the anterior fontanelle is closed, the temporary teeth are cut and the child is beginning to talk and walk, to use judgment and memory and to display independence. Childhood is character ized by active growth and development of the body and mind. Arrest of growth and loss of weight indicate malnutrition. On the other hand, while a very thin baby is abnormal, a very fat child or youth is, as a rule, one whose nutri tion is at fault, or whose diet is too rich or generous.
The preparation of boys and girls for the duties and responsibilities of manhood and womanhood requires especially that their brains, muscles and digestive apparatus shall be strong. Nerve force must be stored not dissipated and coddling is wrong. Their nervous systems are normally very active and sensitive to impres sions, hence nervous disorders and exhaustion are readily induced by overstimulation of the brain, through excitement, too much study, etc. Physical and mental training must go together. A vigorous child is almost constantly in mo tion, either at work or play, and this is as it should be. The same amount of exercise would exhaust an adult. It is well understood that systematic muscular exercise besides hardening the muscles improves the mental strength, that well-developed children take a higher rank in school than those of the same age less devel oped. Abundant out-of-door exercise also de velops the co-ordinating power of muscles and the special senses, induces a greater respiratory range, better oxidation and an increased power of the heart. Thus nutrition is stimulated and a symmetrical development obtained. And this is just as necessary for girls as for boys. Chil dren need sleep oftener and longer than adults. A healthy young baby sleeps nearly two-thirds of the time and a healthy child of seven will often sleep quietly for 12 hours or more. Dis turbed sleep and sleeping with the mouth open indicate some nervous gastric or intestinal dis turbance or the presence of enlarged tonsils.
After the first few years of life the special senses seem to acquire an acuteness more marked than in later life when the perceptions are associated with more complex mental proc esses. Children require much food and the diet should be nutritious, but overloading the stomach, especially with sweets and fruit, may excite general convulsions, vomiting, diarrhoea and alarming fever. A vigorous, healthy boy
often eats, and may require about as much food as the average man. A variable appetite or the habit of eating mainly one class of foods is indicative of innutrition. A properly mixed diet is necessary for health. Sugar (candy, etc.) valuable in reasonable amount, should not be eaten in such quantity as to interfere with the appetite for regular meals. Children, especially those who eat but little sugar, should be taught to cat fat. In childhood the lym phatic system is still active, the glands readily enlarge as the result of irritation or of general disease, especially scrofula. The respiration in early childhood as in infancy is mainly dia phragmatic— the abdomen moves freely. The temperature normally is about 100° F. A sud den high temperature is. much less significant than in the adult, so also is an increase in the rapidity of the pulse. Young children lose heat readily from the surface of the body, and are susceptible therefore to cold') when in sufficiently clad. The line should be carefully drawn between overdressing and the ((harden hie process, and woolen garments except in the hottest weather are advisable.
Owing to the large amount of food con sinned and the detritus resulting from the activ ities of the body — a free discharge of waste by the skin, kidneys and bowels should be facili tated by frequent bathing, the drinking of con siderable pure water and the use of fruit, gra ham bread and green vegetables.
The stomach in children is straighter and more vertical than in adults, but less so than in infants. Vomiting is still easily produced. The small intestine is relatively much longer than in adults, due to the fact that much nour ishment is to be digested.
Children are susceptible to nervous disorders such as chorea and certain forms of paralysis, and to whooping cough, mumps, measles, infan tile paralysis or poliomyelitis, etc., which last are often classed as °children's Spinal deformities are readily induced. Cer tain diseases, such as tuberculosis, are likely to affect a large number of organs at the same time. The recuperative power of a normally healthy child is very great, even in severe dis eases.