near relatives, where
both parents would be inclined to the same weaknesses, has always been
proscribed. However, even with the characteristics of the father
offsetting peculiarities of the mother, it is possible for the traits of
a parent to be reproduced in children, and this applies to mental traits
as well as to physical. In some families there exist tendencies toward
nervous diseases, such as epilepsy and insanity, although it is not
accurate to say that either disease is naturally inherited. It has been
observed that a tendency to cancer, to scrofula, and to rheumatism runs
in certain families, but this is hardly more than saying that in certain
families, where the predisposition in this direction by one parent is
not offset by the tendencies of the other parent, the physical condition
of the child is such as to encourage the development of diseases.

_Age and sex._

As indirect causes of disease, age and sex cannot be overlooked. It is
well known, for instance, that certain diseases belong essentially to
childhood, measles and scarlet fever being markedly prevalent among
children under ten years of age. In fact, it has been said by experts
that if measles could be kept from children under five years old, the
disease would be practically stamped out, since beyond that age they are
less susceptible and the course of the disease is much milder. No
greater mistake can be made than in exposing children to so-called
"children's diseases" because of a desire "to have it over with." Not
only is such exposure foolish, since it is quite possible to escape the
disease altogether if in the first few years of life it is avoided, but
also inviting death, since the mortality of the disease becomes markedly
less and less as the age of the patient advances.

Many of the diseases of children are due to imperfect and incomplete
development; either the lungs or the stomach or some other organ is not
equal to its work, and the child remains an invalid or dies. Many
children die from imperfect nutrition, especially in the second summer,
when teething is at its height, on account of the ignorance of the
mother and on account of unsanitary surroundings. No movement is more
promising in the way of prolonging the lives of children than that
recently inaugurated in New York which undertakes to teach mothers, of
foreign nationality in particular, how to dress, bathe, feed, and bring
up their children.

Another reason why disease occurs