bed-rooms. It is wonderful.

Another great evil in house construction is carrying drains underneath
the house. Such drains are never safe. All house drains should begin and
end outside the walls. Many people will readily admit, as a theory, the
importance of these things. But how few are there who can intelligently
trace disease in their households to such causes! Is it not a fact, that
when scarlet fever, measles, or small-pox appear among the children, the
very first thought which occurs is, "where" the children can have
"caught" the disease? And the parents immediately run over in their
minds all the families with whom they may have been. They never think of
looking at home for the source of the mischief. If a neighbour's child
is seized with small-pox, the first question which occurs is whether it
had been vaccinated. No one would undervalue vaccination; but it becomes
of doubtful benefit to society when it leads people to look abroad for
the source of evils which exist at home.

[Sidenote: Cleanliness.]

4. Without cleanliness, within and without your house, ventilation is
comparatively useless. In certain foul districts of London, poor people
used to object to open their windows and doors because of the foul
smells that came in. Rich people like to have their stables and dunghill
near their houses. But does it ever occur to them that with many
arrangements of this kind it would be safer to keep the windows shut
than open? You cannot have the air of the house pure with dung heaps
under the windows. These are common all over London. And yet people are
surprised that their children, brought up in large "well-aired"
nurseries and bed-rooms suffer from children's epidemics. If they
studied Nature's laws in the matter of children's health, they would not