unities that destroy the
eggs of certain mosquitoes; and many other facts in regard to health
have been learned, a great change has come over the popular belief. It
is seen that, to a great extent, man holds his own fate and is
responsible for his own suffering, and people are eager to learn more
about their own bodies, how to cure them and how to keep them well.

This knowledge has already done much to prolong life. The average length
of life in India, where no attempt is made to check disease, is
twenty-five years. In England the length of life has doubled in a few
generations. In Sweden, where the people live a sanitary life, the
average is over fifty years, in this country, forty-five years.

Insurance companies and benefit societies keep close watch of their
members and they report that a person ten years old may now count on
living to be sixty years of age. That is the average age, whereas a
hundred years ago the average expectation of life at that age was only
fifty-three years.

And this is true in spite of the fact that people have been crowding
into cities, that they are living on richer foods, taking less exercise
in the open air, living in houses which shut out the fresh air, and
doing dozens of other things that have tended to lower rather than to
raise the average.

We can scarcely realize the possibilities of life if, with all the
present scientific knowledge of disease and health, we could have a
generation of people living according to nature's laws.

Life can be not only lengthened but strengthened. There are many
instances of frail, feeble children who have developed into
exceptionally strong men and women. One of the most noted is Von
Humboldt, the great scientist, who as a child was very weak physically,
and, he himself says, was mentally below the average, but who lived to
the age of ninety, and developed one of the greatest minds of his
century.

Doctor Horace Fletcher, noted for his theories in regard to eating, was
rejected at the age of forty-six for life insurance but so strengthened
his constitution by careful living that by the time he was fifty he not
only obtained his life insurance but celebrated his birthday by riding
one hundred and ninety miles on his bicycle.

If we could imagine a person who all his life had lived in a locality
where the air was pure; in a house where fresh air entered day and
night, and which was heated to a uniform temperature; whose food had
always consis