A perfectly accurate comparison between the growth of girls and boys is not obtainable from the tables, for the girls belonging to Table II. were not drawn exclusively from one class. But the table shows that girls attain their full height earlier than boys by between two and three years, namely at 17 years, and that their mean height is from 4 to 7 inches less than men. Even at birth there is a difference in height and weight between male and female children to the advantage of the former. The difference in weight between the two sexes and in chest-girth is also marked. What is specially worthy of note, however, is that it is between the 11th and 13th years that growth is most rapid in girls both in height and weight. After 14 growth, which began to lessen the year before, rapidly diminishes, and is reduced to very little after 16. This rapid falling off in growth is coincident with other changes of great importance discussed in Sect. In the tables the figures between the years when growth becomes most rapid and then falls off are given in black type for the sake of emphasis.
The Relation of Height to Weight. It is of importance to notice that increase in weight should occur in a regular way with in crease in height. The following table is given by Dr. Percy Poulton in the Lancet of Oct. 16, 1880, as a reliable working standard. It is de duced from the results of observations of the same children who were examined at least once annually. The children were selected as average children of healthy well-to-do parents, brought up with suitable food and surroundings, giants and dwarfs being excluded.
The general conclusions will best be given in Dr. Boulton's own words. "I find," he says, "that average English children, brought up under favourable circumstances, grow from 2 to 3 inches a year. A growth of less than 2 inches or over 3 should excite apprehension. The for mer would indicate arrested development, and the latter a rate of growth beyond the powers of average children. Rate of growth should be regular, and, being so, prognosticates future stature, because the healthy child that grows 2 inches a year passes 5 feet at about 15, which indicates a short stature (i.e. if a male about 5 feet 6 inches, female about 5 feet 1 inch). The healthy child growing 2i inches a year is 3 feet 2 inches at 3 years, and passes 5 feet at 13 to 14 years. Such child will be a medium-sized adult (i.e. if a male about 5 feet 8 inches, female about 5 feet 3 inches). The quick-growing healthy child that accomplishes 3 inches a year passes 5 feet at 10 or 11, and eventually makes a tall adult (i.e. if a male about 5 feet 10 inches, female about 5 feet 5 inches). . . . Of course one meets with many variations, but these vari ations are,.I believe, always abnormal. Some children seem to do their growing by fits and starts, the common diseases of children arrest ing, for the time, their progress, which is made up for afterwards by a supreme effort. Such growth is unnatural and often very detrimental. I believe, then, that every healthy child has its own regular rate of growth of 2, 21, or 3 inches a year, from which it has no right to vary more than inch a year." "Next as to weight for height, whether a child grows 2, 2-i, or 3 inches a year, weight for height should be, in each case, identically the same; and all children should grow broad in proportion to their height. Between 3 and
4 feet the increase in weight should, I find, be 2 pounds per inch, and between 4 and 5 feet 2i pounds per inch." . . .
"Some children exceed these weights (those given in Table IV.) that are by no means giants, and really healthy, well-nourished children of healthy parents and favourable surroundings generally attain these averages. But what of children that fall below the standard? I find that there is a 7-pound margin of safety, and that children falling more than 7 pounds below this standard are devoid of reserve capital on which to draw, and, consequently, they succumb quickly to many constitutional diseases. This, therefore, may be called the preventive-medicine margin, beyond which lies the dangerous land of cachexia" (a depraved condition of body).
"Arrest of growth or loss of weight precedes so many diseases that it may be looked upon as a danger signal ; and, if the caution is noticed before the disease point is reached, catastrophe may frequently be prevented." These tables are given as standards for refer ence, and brief suggestions will be given in closing this section as to their method of use.
Each child should be weighed and its height taken once a month, or at least once a quarter. Reference should then be made to Table I. or III. in the case of boys, according to the class to which the child belongs, the labouring or more favoured class, or to Table II. in the case of girls. It will thus be seen whether the child reaches the standard for its age. The column of the table is taken headed with the age of the child at its last birthday; and in that column will be found the height, weight, and chest-girth to which it ° should reach. The results of each weighing and measuring should be noted in a book kept for the purpose, the date being accurately entered. The increase that has taken place since the last trial should be noted and compared with the standard in the tables. Lastly, the height of the child should be referred to Table IV., and it should be noticed whether the weight reaches to that mentioned in the table as proper to the particular height.
Of course there will be variations. Any con siderable variation, however, and specially any sudden variation, should lead to careful con sideration of all the child's circumstances, its food, the fresh air and exercise obtainable by it, the amount of school and other work, &c. Some change in these may at once be suggested. If no such circumstance seems to account for the departure from the rule, medical advice should be sought.
Especially between the ages of 11 and 17 should the results of the weighing - chair and measuring-rod be carefully watched. They will throw light on the question of over-pressure at school, and, if their warning is accepted, will do much to prevent it. Every school ought to have a room set apart and equipped for the weighing and measuring of the pupils. The standards of weight and height should be painted on the walls, and each pupil's height, weight, and chest-girth should be registered at regular periods. Educa tion would then have a better chance of being conducted on physiological principles, and with some regard to the physical development of the pupils.