SPRAYING PEAGHES WITH ARSENICALS. 213 
as needed to form at first a thick paste and then gradually a thin 
paste. The lime will supply enough heat to boil the mixture sey- 
eral minutes. As soon as it is well slaked water should be added to 
cool the mixture and prevent further cooking. It is then ready to 
be strained into the spray tank, diluted, and applied. 
The stage at which cold water should be poured on to stop the 
cooking varies with different limes. 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 for 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 intense 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. The mixture should be strained to take 
out the coarse particles of lime, but the sulphur should be carefully 
worked through the strainer. 
DIRECTIONS FOR USING ARSENATE OF LEAD. 
Many experiments have shown that well-made arsenate of lead is 
much the safest of all arsenicals at present available for use on the peach. 
Arsenate of lead is to be found on the market both as a powder and 
as a putty-like paste, which latter must be worked free in water 
before it is added to the lime-sulphur mixture. The paste form of 
the poison is largely used at the rate of about 2 pounds to each 50 
gallons of the lime-sulphur wash and is added, after it has been well 
worked free in water, to the lime-sulphur spray previously prepared. 
As there are numerous brands of arsenate of lead upon the market, 
the grower should be careful to purchase from reliable firms. A 
decided change in color will result when the arsenate of lead is added 
to the lime-sulphur mixture, due to certain chemical changes which, 
in the experience of the writers, do not injuriously affect the fungi- 
cidal and insecticidal properties of the spray or result in important 
injury to the foliage. 
In large spraying operations it will be more convenient to prepare 
in advance a stock mixture of arsenate of lead, as follows: Place 100 
pounds of arsenate of lead in a barrel, with sufficient water to work 
into a thin paste, diluting finally with water to exactly 25 gallons. 
When thoroughly stirred, each gallon of the stock solution will thus 
contain 4 pounds of arsenate of lead, the amount necessary for 100 
