174 The Sweet Potato 



applied in a room or bin that is practically air-tight. 

 Fire must be kept away as this is very inflammable. 



SPEAT MACHINERY 



Sprays are best applied by the use of proper instru- 

 ments, a few of which will be discussed here. For the 

 grower that has only a few rows, a small hand sprayer 

 or atomizer may be used. These ordinarily hold about 

 a quart and may be bought at almost any hardware 

 store. . These are usually of glass or tin. 



Knapsack pumps are most suitable for the farmer who 

 has a small patch, from one-half to several acres. 

 These are usually made of galvanized iron or copper and 

 are strapped on the back so that the operator pumps 

 with one hand and holds the nozzle with the other.. 

 They ordinarily hold from 2 to 4 gallons. The pump 

 should have a good agitator or mixer. Bordeaux mix- 

 ture will soon eat out the pump. 



Compressed air sprayers are small, handy and very 

 efficient. The capacity usually runs from 2 to 4 gallons, 

 and a pressure of several pounds is maintained by a 

 small air pump extending down into the tank. The 

 spray is released by turning on the faucet near the noz- 

 zle. A tank of spray material may be applied with 

 two or three pumpings. These are fitted with a strap 

 so that they can be carried over the shoulder with ease. 

 The top should be screwed on and not clamped on over 

 a rubber gasket. 



Barrel pumps are the most serviceable and popular 

 for the average farm. Much more work can be accom- 

 plished with these, and very efiiciently. These barrels 

 hold from 50 to 60 gallons, and of course have to be 



