" } {
8 months 25 " 181/4 " } {Gained 1/2 in. a month.
9 months 251/2 " 183/4 " } {
10 months 26 " 193/4 " } {Gained about 1 lb. a month.
11 months 261/2 " 201/2 " } {
1 year 27 " 211/2 " } {Treble original weight.

2 years 31 " 27 " } {
3 years 35 " 32 " } {Gain 4 in. a year.

4 years 371/2 " 36 " } Double original length.
5 years 40 " 40 " } {Gained 3 in. and 4 lbs.
} {a year.

6 years 43 " 44 " } {Gained 2 in and 4 lbs.
7 years 45 " 48 " } {a year.

8 years 47 " 53 " } {Gained 2 in. and 5 lbs.
9 years 49 " 58 " } {a year.

10 years 51 " 64 " } {Gained 2 in. and 6 lbs.
11 years 53 " 70 " } {a year.

12 years 55 " 79 " }
13 years 57 " 88 " }
14 years 59 " 100 " } {Gained 2 inches and
15 years 61 " 109 " } {about 9 lbs. a year.
16 years 63 " 117 " }

GENERAL DEVELOPMENT

The accompanying illustration (Fig. 14), taken from Dr. Yale,
represents the developmental changes at one, five, nine, thirteen,
seventeen, and twenty-one years. Each figure is divided into four
equal parts, and as we watch the development from the baby who at one
year, as Dr. Yale says, is four heads high, at the age of twenty-one
the legs and the trunk have much outgrown the growth of the head, so
that at this age the head is only two-thirteenths or less of the whole
length of the body. The legs have grown more rapidly and equal
one-half the entire body length. The trunk has not kept pace with the
legs, for as you will see from the diagram the line reaches the navel
of the child in one year, while in the adult it is much lower. The
rapid growth of the legs is accomplished after nine years of age.

[Illustration: Fig. 14. Developmental Changes]

The proportions of the head, chest, and abdomen are exceedingly
important in the growing child. At the end of the first year the head,
chest, and abdomen are about uniform in circumference. The head may
measure one-fourth of an inch more, but the chest and abdomen should
both measure eighteen inches in circumference at this time. Should
the head or the abdomen be two inches larger than the chest; the
attenti