SMALL HAND PUMPS 



93 



Knapsack Pumps 



Knapsack pumps consist of an oblong tank furnished with straps 

 for hanging on the back, and provided with a small, inclosed 

 pump, the handle of which projects forward over one's shoulder. 

 They are not in general favor. The apparatus is fairly heavy 

 to carry, and is likely to 

 spill liquid down one's back. 





Fig. 59. 



An automatic sprayer. 

 Original. 



Automatic Sprayers 



Automatic sprayers are air-tight cylinders designed to be carried by 

 hand. The cylinder is filled partly full of the spray material, the top 

 fastened on, and by means of a self-contained pump air is forced in 

 until the liquid within is under pressure. A valve allows the spray to 

 be driven out through the nozzle as desired. The apparatus is handy, 

 and desirable for garden work. Its principal disadvantage is the lack of 

 an agitator. Only the brass sprayers should be purchased. Those in 

 which the tank is made of iron, while cheaper, will not give satisfaction. 



A light extension rod may be attached to the cylinder, and the 

 apparatus used for spraying small trees, if only a few are to be 

 treated. 



