Insect and Fungous Enemies of the Grape. 67 
The stage at which cold water should be poured on to stop the 
cooking varies with different grades of lime. Some limes are so 
sluggish in slaking that it is difficult to obtain enough heat from 
them to:cook the mixture at all, while other limes become intensely 
hot on slaking, and care must be taken not to allow the boiling to 
proceed too far. If the mixture is allowed to remain hot 15 or 20 
minutes after the slaking is completed the sulphur gradually goes 
into solution, combining with the lime to form sulphids, which are 
injurious to peach foliage. It is therefore very important, especially 
with hot lime, to cool the mixture quickly by adding a few buckets 
of water as soon as the lumps of lime have slaked down. The in- 
tense heat, violent boiling, and constant stirring result in a uniform 
mixture of finely divided sulphur and lime, with only a very small 
percentage of the sulphur in solution. It should be strained to take 
out the coarse particles of lime, but the sulphur should be carefully 
worked through a strainer. The mixture can be prepared in larger 
quantities if desired, say, enough for 200 gallons at a time, making 
the formula 32 pounds of lime and 32 pounds of sulphur to be slaked 
with a small quantity of water (8 or 10 gallons) and then diluted 
to 200 gallons. Arsenate of lead and nicotine solution may be 
added to this mixture, exactly as with Bordeaux mixture. Soaps 
should not be used in lime-sulphur sprays. 
KEROSENE EMULSION. 
Kerosene emulsion has long served as a standard spray for the con- 
trol of soft-bodied sucking insects, especially aphids or plant-lice. 
If well made and properly diluted it will give satisfactory results 
for this purpose. Jt should never be combined with lime sulphur. 
A good stock solution of kerosene emulsion containing 66 per cent 
of oil may be made according to the following formula: 
Kerosenen(coal olla: Oil) US 22s ee ee gallons__ _ 2 
Fish-oil or laundry soap (or 1 quart soft soap) —~--_-___~_ pound__ 4 
ASH ee, owe ss SN ee Pe ee en |e) Se ee ee callonesy, » i! 
First dissolve the soap in boiling water, then remove the vessel 
from the fire. Immediately add the kerosene and thoroughly agitate 
the mixture until a creamy solution results. The stock solution may 
be more conveniently made by pouring the mixture into the tank of 
a spray pump and pumping the liquid through the nozzle back into 
the tank for some minutes. The stock solution, if properly made, 
should last for some time, but it is better to make it up as needed. 
Do not dilute until ready to use. To make a 10 per cent spray (the 
strength for trees in foliage) add for each gallon of the stock solu- 
tion about 53 gallons of water. For 20 and 25 per cent emulsions 
(for use on dormant vines) use, respectively, about 24 and 1% gallons 
