Sunemary. 377 
by completing pwups and appliances. Give particular 
attention to a eouvenient wagon outfit. 
6. The Bordeaux mixture need not be made up 
at each using in the exact) numbers of the formula. 
The copper sulfate may be permanently dissolved in 
water and the lime may be slaked. When the mix- 
ture is prepared, the stoek solution of vitriol is di- 
luted, the lime added, and the tank filled to the 
required amount. 
7. Spraying is of small account unless the opera- 
tor understands precisely what he sprays for. 
8. The time to spray is when the operation is 
needed to protect the plant. This will vary, there- 
fore, with every season and every different pest. In 
general, apples and pears need spraying twice, first 
when the fruit-buds open, but before the flowers 
expand, and again when the blossoms fall. 
9. The presence, of soluble arsenic in Paris green 
may be determined by a test with sulfuret of hy- 
drogen. 
10. Pure Paris green dissolves in ammonia, giv- 
ing a rich, deep blue lquid. 
