24 DISEASES OF DOMESTICATED BIRDS 
usually employed in the strength of 1 part to 1000 parts of water. 
It is available in the form of tablets mixed with ammonium chloride 
to facilitate solution in water. A tablet may be added to a certain 
specified amount of water to make a disinfectant of a definite 
strength. Bichloride of mercury has the disadvantage of attacking 
metals and its activity is seriously impaired by contact with albu- 
minoid substances. Its poisonous nature is some disadvantage. 
Whitewash. Whitewash is made by adding about one pint of 
water to each two pounds of freshly burned lime. The vessel con- 
taining the mixture is covered and allowed to stand for about an hour 
while slaking occurs. Water is then added to the mixture until it 
is thinned to such a consistency that it may be readily applied. 
Weather proof whitewash may be made as follows: Slake one 
bushel of quicklime in twelve gallons of hot water. Dissolve two 
pounds of common salt and one pound of zine sulphate in two gal- 
lons of boiling water. Pour this mixture into the slaked lime and 
add two gallons of skim milk, mixing thoroughly. 
Whitewash has feeble disinfectant powers, but is useful in im- 
proving the illumination of interiors. To a certain extent it covers 
up infective material and fills up the smaller cracks which might 
harbor parasites. 
The value of scattering air slaked lime about poultry houses is 
questioned in view of the. irritation of the eyes and air passages 
induced by the dust. 
Application of disinfectants. The frequency with which poul- 
try houses are disinfected warrants investment in some form of 
pump. For the smaller establishments, a pump built to be used 
‘in a pail may suffice. In larger poultry farms a pressure spray 
pump mounted in a barrel on wheels forms a very convenient outfit. 
CLEANLINESS OF FOOD AND DRINKING WATER 
Feeding troughs may be provided with a cover of slats in the 
form of a peaked roof. Birds will be compelled to reach through 
the slats to eat mash, and cannot walk in the feed. Sanitary water 
fountains entirely prevent birds from walking in the drinking water. 
Further protection of the drinking water by the use of potassium 
permanganate is very generally practiced. A saturated solution of 
this substance is prepared in a large bottle or jar and is kept con- 
veniently near the drinking fountain. When water is drawn for the 
birds, enough of the stock solution is added to impart a deep wine 
color to the water. 
