les, and 12-13 in males, where
it must be nearly doubled; afterwards it may be continued, and will be
found very nearly correct up to the age of 18 or 19, when the growth
proceeds very slowly. At an equality of age the male is generally
heavier than the female. Towards the age of 12 years only an
individual of each sex has the same weight. The male attains the
maximum weight at about the age of 40, and he begins to lose it very
sensibly toward 60. At 80 he loses about 13.2328 lbs., and the stature
is diminished 2.756 inches. Females attain their maximum weight at
about 50. The mean weight of a mature man is 104 lbs., and of an
average woman 94 lbs. In old age they lose about 12 or 14 lbs. Men
weigh most at 40, women at 50, and begin to lose weight at 60. The
mean weight of both sexes in old age is that which they had at 19.

When the male and female have assumed their complete development they
weigh almost exactly 20 times as much as at birth, while the stature
is about 3-1/2 times greater. Children lose weight during the first
three days after birth; at the age of a week they sensibly increase;
after one year they triple their weight; then they require six years
to double their weight, and 13 to quadruple it.

It has been computed that nearly two years' sickness is experienced by
every person before he is 70 years old, and therefore that 10 days per
annum is the average sickness of human life. Till 40 it is but half,
and after 50 it rapidly increases. The mixed and fanciful diet of man
is considered the cause of numerous diseases from which animals are
exempt. Many diseases have abated with changes of diet, and others are
virulent in particular countries, arising from peculiarities.

Human Longevity.--Of 100,000 male and female children, in the first
month they are reduced to 90,396, or nearly a tenth. In the second,
to 87,936. In the third, to 86,175. In the fourth, to 84,720. In the
fifth, to 83,571. In the sixth, to 82,526, and at the end of the first
year to 77,528, the deaths being 2 to 9. The next four years reduce
the 77,528 to 62,448, indicating 37,552 deaths before the completion
of the fifth year.

At 25 years the 100,000 are half, or 49,995; at 52, one-third. At
58-1/2, a fourth, or 25,000; at 67, a fifth; at 76, a tenth; at 81, a
twentieth, or 5,000; and ten attain 100. Children die in large
proportions because their diseases cannot be explained, and because the
organs are not habituated to the function