233 WATCHING 
AND SPRAYING 
proportion and ways, but it is not so easy to 
know how strong it is as with Paris green, and 
it is being used less and less each year. 
Another preparation is arsenite of soda, 
which is made of white arsenic, two pounds; 
carbonate of soda (washing soda) eight pounds; 
water two gallons. These must be boiled in an 
iron kettle, which should not be used for any 
other purpose, for about fifteen minutes, or 
until the arsenic dissolves. Some water will 
evaporate during boiling, so, before bottling, add 
enough to make the full two gallons. This 
will keep a long time if tightly corked. To make 
a spraying solution add one-half pint to 25gallons 
of water. The quantity given is, therefore, 
enough to make 8 barrels of 50 gallons each. 
Unless mixed with Bordeaux, add two pounds 
of slaked stone lime to each barrel. Be sure to 
mark your bottle of solution plainly, ““POISON.”’ 
Arsenate of lead clings to foliage better than 
any other arsenical poison, and since it does 
not burn foliage it can be used alone, in the 
proportion of from one to five pounds to 50 
gallons of water. It was first used in 1892 
against the gypsy-moth and is annually grow- 
ing in favor. 
All insects which feed on the outside of plants 
are divided into two classes—the chewing or 
