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THE APPLE 



and the stone lime are dissolved in separate vessels and then 

 mixed, they will remain in suspension much longer than when 

 dissolved together. 



10. The thorough straining of the material as it is poured into 

 the spray tank is essential. This will prevent much trouble with 

 clogged nozzles. 



1 1 . Care must be taken in the selection of a nozzle. Defective 

 nozzles throw too coarse a spray. A fine spray is best, but it must 

 be ejected with force. 



Careful spraying is necessary when the winds are high. Work 

 must often be done while a strong wind is blowing, in which case 

 the trees should be sprayed entirely from the windward side. The 

 wind will assist in driving the liquid through the trees. 



The advice usually given is to spray against the wind. However, 

 it is much easier to say this than actually to perform the work. No 

 available figures on this point were at hand until R. \V. Westlake, 

 New York, made some careful experiments along this line. The 

 results are shown in the following table : 



