32 BULLETIN NO. 1, DIVISION OF ENTOMOLOGY. 
I found that kerosene combined better with dense and rather warm 
solutions than if the same were cold or much diluted; and that the . 
zamia and soap solutions were easier to use if kept at a temperature of 
about 100° to 120° F. 
EMULSIONS. 
1. Four pounds whale-oil soap were dissolved in one gallon of water, 
with heat; to this kerosene was added gradually till it was found that 
one gallon kerosene made a good emulsion, capable of being diluted to 
1 per cent, without at once disintegrating. 
One gallon of this mixture containing 50 per cent. kerosene costs 30 
cents. In several experiments with Lecanium on small trees I tried a 
saturated solution of tobacco, two pounds to the gallon, to dissolve the 
soap. This gave good results, but from the extra expense and trouble 
I abandoned its use. 
2. Four pounds rosin soap, common bar or yellow soap, were dissolved 
in one gallon water. One gallon kerosene gradually added, with con- 
stant agitation, made an emulsion costing 26 cents per gallon. 
The greater the percentage of rosin in the soap the better emulsion I | 
found it made, which would indicate that such a soap for this purpose 
would no doubt be a valuable article in this market. 
3. Six pounds fresh zamia root were grated and boiled in 3 gallons 
water, made alkaline by adding 3 ounces ‘ sal-soda.” After boiling an 
hour, the mucilage was strained, and while hot one gallon kerosene added 
gradually, with considerable agitation. Enough warm water was added 
to make the solution when finished measure four gallons. This formed 
a smooth, creamy emulsion, quite stable, containing 25 per cent. kero- 
sene, and costing 5 cents per gallon. 
MILK EMULSIONS. 
Ist. With fresh milk. 
4, Emulsions containing 25 per cent., 50 per cent., 33 per cent. kero- 
sene were each made, and gave good results. Milk, either fresh or sour, 
could be used with about the same action. 
2d. With condensed milk. 
This for many reasons was found most generally available. 
Two solutions were made: 
a. One pound condensed milk diluted with three pints hot water; to 
this one gallon kerosene was gradually added, with constant stirring. 
As soon as the emulsion began forming, four pints water were added, 
and the emulsion completed with brisk agitation. One gallon of this 
contained 50 per cent. kerosene. Cost, 22 cents per gallon. 
