Spraying Devices and Machinery. 215 



not being smaller than 2| inches, and in some it is as large as 

 5 inches in diameter. These pumps are little used, as they 

 seem to be harder to operate, and they are limited in their use 

 more than the forms adapted to barrels. 



FIG. 29, Spray pump, with large air chamber ; the paddle at the bottom of the 

 barrel acts as an automatic agitator. 



In some localities, semi-rotary pumps (Fig. 31) are in demand, 

 no other form being thought equally effective. The action of 

 these pumps, when new, leaves little to be desired. They are 

 easily worked and powerful, and at first appear to approach the 



