Spraying Devices and Machinery. 213 



with the water. But, if the barrel is on end, the sediment col- 

 lects in an even layer over the entire bottom, and it is much 

 more difficult to maintain an even mixture. Large tanks are 

 unsatisfactory in this respect, since the bottom is generally flat, 

 and it is difficult to reach all the sediment with the agitator. 

 When power sprayers are used, and the horse does the pump- 



FIG. 27. A compact and powerful spray pump. 



ing, it does not make so much difference if the labor is harder, 

 and the agitator can be attached to a moving part of the pump 

 with very satisfactory results. 



Fig. 27 represents a type of pump sold by several manufac- 

 turers, which answers most of the requirements above men- 

 tioned. The air chamber is in the piston rod, where it is 

 entirely out of the way, yet it is large enough for all practical 

 purposes. These pumps are exceedingly compact, powerful, and 



