38o 



ECONOMIC ENTOMOLOGY 



The essentials of a good nozzle are: 



1 . Simple in construction, adjustable, light and free from projecting 

 parts. 



2. Not liable to dribble on account of wearing of packing or springs. 



3. Easy to clean. 



4. Not liable to clog. 



5. Giving a uniform spray when pressure is constant. 



Fig. 248. — Spraying large orchard and shade trees by means of a tank platform and 



two lines of hose. 



NOZZLES 



Three types of nozzles are used in spraying operations — the Bor- 

 deaux, Verm or el and Disk. 



The Bordeaux nozzle has its opening adjustable by means of a 

 stop-cock so that various forms of sprays can be employed. The 

 spray is made by a straight stream hitting a lip and breaking up into 

 a fan-shaped spray. It is well adapted for vineyard work where Bor- 

 deaux and arsenicals are used. When clogged it can be readily cleaned 

 by reversing the stop-cock. "Perfecto," "Niagara," "Seneca" 

 are trade names. 



The Vermorel nozzle has a central opening in front of a chamber, 

 into which the Hquid enters at a tangent. It gives a fine cone-shaped 



