ADV \.\ i \(.i ;s rxh! i: i in i m im;u\ in SYS1 EM 
63 
his measurements and calls out the dosage. The two men then 
measure out the required amount of chemicals and dose the tree (fig. 
). While they are thus engaged the estimator li 
as moved on t<> 
the next tree, determined the proper dosage, and holds the generator 
in readiness when the cart is brought up. He l lien calls out the 
dosage with which the tree is to be treated. This procedure contin- 
ues in like manner until the entire row Is fumigated. 
Outfits employing tins system have, on an average, been fumigat- 
ing a complete set of 32 tents in from forty to forty-five minutes. 
This would appear to demonstrate that the system is entirely practi- 
cable from the standpoint of time economy, as tents an* usually 
required to he left on the tree one hour. 
ADVANTAGES UNDER THIS SYSTEM. 
First. — The element of guesswork in estimating dosage and the 
consequent waste of cyanid are eliminated, since the dosage is deter- 
mined according to a uniform method in all cases. If a dosage of suf- 
ficient strength to destroy 90 per cent of the purple scale is used, 
practically 90 per cent of the purple scale is killed on c\^\y tree 
throughout that orchard not 90 per cent on some trees and 50 per 
cent, more or Less, on others, which has occurred at times under the 
old method. Or if a dosage strength just sufficient to eradicate the 
pest i> employed, a. like result will occur throughout the orchard and 
there will he no great waste of cyanid by reason of man} trees 
receiving a larger dosage than was necessary. 
J 
