Circular 21 - Insecticides and Subadiary Materials 42 
possessing a characteristic, somewhat dis- 
agreeable odor suggestive of iodine. It melts 
at about 120° C. (248 F. ) and is only slightly 
soluble in water. Its chief uses are medicinal. 
Iodoform is sold at a price of $3.95 
to ^4.10 in 100-pound drums and in jars at 
$4.20 per pound. 
Available on contract: see Class 51, 
General Schedule of Supplies, Procurement 
Division, Treasury Department. 
KEROSENE 
Of the many petroleum products, kero- 
sene (kerosene oil) probably has been used 
more extensively than any other in connection- 
with the control of insect pests. Kerosene 
may be applied to the shoes and outer clothing 
in place of sulfur to repel chiggers and if 
applied to the body before bathing it facili- 
tates their removal. It may be used alone or 
in combination with turpentine for controlling 
powderpost beetles by dippin£r the infested 
v/ood. Bedbugs can be killed with kerosene or 
a similar liriit petroleum oil or they may be 
prevented from infest in.^^ beds by placing: the 
lec:s of the bed in shallow dishes of kerosene. 
v/hen combined with an oil extract of pyrethrum 
(containing 2 percent pyrethrins) at the rate 
of 1 gallon of pyrethrum extr:ict to 19 gallons 
of kerosene or siiiilar oil, a contact spray is 
made which is useful in killing: flies, mosqui- 
toes, ticks, cockroaches, and other insects. 
An emulsion of kerosene, soap (or other enail- 
sifier), pjTethrum extmct, and "«:ater is an 
effective mosquito larvicide ivhen applied to 
the surface of v;ater pools or other "breeding 
