FUNGICIDES, PREPARATION AND APPLICATION 435 
pare stock solutions, proceed as follows: dissolve the re- 
quired amount of copper-sulfate in water in the proportion of 
one pound to one gallon several hours before the solution is 
needed, suspending the copper-sulfate crystals in a sack near 
the top of the water. A solution of copper-sulfate is heavier 
than water. As soon, then, as the crystals begin to dissolve 
the copper solution will sink, bringing water again in contact 
with the crystals. In this way the crystals will dissolve much 
sooner than if placed in the bottom of the receptacle of water. 
In case large quantities of stock solution are needed, two pounds 
of copper-sulfate may be dissolved to one gallon of water. 
Slake the required amount of lime in a tub or trough. Add 
the water slowly at first, so that the lime crumbles into a fine 
powder. If small quantities of lime are used, hot water is 
preferred. When completely slaked or entirely powdered, 
add more water. When the lime has slaked sufficiently, 
add water to bring the mixture to the proportion of one pound 
of lime to one gallon of water. These stock mixtures should 
not be allowed to dry out and should be kept covered. 
To make the bordeaux, use five gallons of stock solution of 
copper-sulfate for every fifty gallons of bordeaux required. 
Pour this into the tank. Add water until the tank is about 
two-thirds full. From the stock lime mixture take five gallons 
of the thoroughly stirred lime-milk for each fifty gallons of 
the mixture required. Dilute this a little by adding water, 
and strain into the tank. Stir the mixture and add water to 
make the required multiple of fifty gallons. Experiment sta- 
tions often recommend the dilution of the copper-sulfate solu- 
tion and the lime mixture each to one half the required amount 
before pouring together. This is not necessary, and is often 
impracticable for commercial work. It is preferable to dilute 
the copper-sulfate solution. One should never pour together 
the strong stock mixtures and dilute afterwards. Bordeaux 
mixture of other strengths as recommended is made in the 
