SELECTING MACHINERY AND EQUIPMENT 325 



Ions per minute at 250 pounds pressure, depending upon the 

 construction details already mentioned. They are frequently 

 arranged in pairs or in clusters of three or even more. When 

 the nozzles are so arranged, the cone of spray 

 is narrowed and the driving power is in- 

 creased as the nozzles are brought closer to 

 each other, the air resistance being decreased. 

 At least one experiment station recommends 

 a set of disk nozzles on a spray rod, 8 to 10 

 feet long, in preference to the spray gun. 



When rather coarse materials in suspen- 

 sion must pass through the nozzle, the larger 

 sizes of disk apertures should be used. Angle 

 disk nozzles are helpful in reaching the under 

 surfaces of the leaves and in giving better 

 direction to the spray, and they enable the 

 operator to keep out of the spray himself. 

 They constitute standard equipment. 



9. The Gun. The spray gun is a disk 

 nozzle or multiple nozzle of large capacity ^-^^^^^ ^^^-^^jfco ) 

 with a range that may be changed at will. ^ ^ ^ , 

 T X .f . 1 ..1 A' ^ u^ lis- Bamboo 



in enect, it is a nozzle with an adjustable ^^^^y ^jth 



eddy chamber in the form of a plunger. The aluminum core, 

 gun may be entirely shut off by turning the 

 plunger up against the exterior disk. As the plunger is with- 

 drawn and the eddy chamber increases in depth^ the cone of 



Fig. 119. A powerful one-nozzle spray-gun of modem design. 



spray becomes narrower, with coarser particles and greater 

 driving range. 



The range and type of spray may be changed by a partial 

 turn of the hand: foliage near at hand may be coated with a 



