HYGIENE AND SANITATION 21 
be hitched to the building to move it as desired. A very desirable 
method of securing fresh soil is to move chicken houses in harmony 
with a crop rotation system. In this manner a given area is cropped 
for three or four years after chickens have occupied it, before the 
land is used for birds again. When quarters are so cramped that 
no change can be made in the chicken yards, deep plowing is of 
some advantage in turning up fresh earth and covering contaminated 
soil. Small areas may be sprinkled with lime, or be thoroughly 
soaked to some depth by the liberal application of a disinfectant. 
LOCATION AND CONSTRUCTION OF POULTRY HOUSES 
Dampness is very injurious to fowls, and consequently the build- 
ings should be located with reference to securing good drainage after 
rains. Where choice is possible, sandy soil should be chosen on 
account of its permeability to water. Provision should be made to 
secure free ventilation without drafts of air. No especial effort 
need be made to secure warmth in a poultry house in the daytime 
even in a severe climate. The building should be so located as to 
permit the unobstructed illumination of the interior by sunlight. 
The frequency with which poultry houses must be cleaned and 
sprayed with parasiticides should be borne in mind when they are 
being constructed. Any structural detail which interferes with the 
free access to any part of a house by a man, should be avoided for 
it will interfere with routine cleaning. The habit displayed by 
mites, of collecting in cracks, should be recognized in providing 
buildings with a minimum of such places where vermin may col- 
lect. Nest boxes, perches and similar fittings should not be per- 
manently attached to the building, but should be readily removable 
for cleaning and spraying. 
Certain details of construction will at least constitute impedi- 
ments to the dissemination of parasites and infective material from 
bird to bird. Thus, stretching chicken wire under the roosts will 
largely prevent birds from coming in contact with droppings in the 
roosting quarters. 
In houses designed for laying hens in a cold climate, each bird 
should be provided with from three to four square feet. Exercise, 
which is absolutely essential to health, will be provided by mixing 
some of the feed with clean litter on the floor. 
