Investigations of the Department of Agriculture have disclosed the
fact that many cases of typhoid fever and malaria, often considered
unaccountable in their origin, are the result of the germs being
carried by the house-fly. Screens, flypaper, and poisons are all very
well, in a small way, but to free the place of flies means getting rid
of the conditions which produce them. Leaving out the manure pile (see
MANURE PITS, page 45), the favorite breeding-place of flies is the foul
floors of the cow and horse barns. The barn can be almost entirely rid
of flies by building floors and manure pits of concrete.