Circular 21 - Insecticides and Subsidiary Materials 45 
LIME 
Lime (hydrated, CalOH)^) may be used as 
a diluent for paris green to make a dust for 
the control of malaria-carrying mosquito 
larvae. One part of paris green is usually 
mixed with ^ or 5 parts of lime. It is also 
used in reducing the acidity of other arseni-- 
cals for spray purposes. The ordinary hydrated 
mason *s lime as commercially marketed is 
satisfactory for this purpose. 
Hydrated lime is a white, soft powder 
which has a slightly bitter, alkaline taste. 
It absorbs carbon dioxide (COp) from the air, 
thus changing to calcium carbonate (CaCOo). 
The hydrate is used extensively industrially 
in mortars, plasters, and pastes, for dehairing 
hides, in water paints, and for an agricultural 
lime for reducing the acidity of soils. 
Caution : The dust if inhaled is some- 
what irritating to the respiratory passages. 
Keep containers well closed. 
Hydrated lime is obtainable in ton lots 
packed in paper bags at ;i?8.50 to $13.00 per 
ton depending upon location. 
Available on contract: see Class 59, 
General Schedule of Supplies, Procurement 
Division, Treasury Department. 
