32 



BULLETIN 1243, U. S. DEPARTMENT OF AGRICULTURE. 



The hand sprayer (fig. 14) referred to is a 3-gallon capacity, com- 

 pressed-air type, which it is estimated produces from 40 to 65 pounds 

 pressure if pumped at intervals of 100 feet of row. 



Fig. 11. — Power sprayer used in experiments against the Mexican bean beetle, showing arrangement 

 of nozzles and device for raising the boom. 



The knapsack type of hand bellows duster used is illustrated in 

 Figure 15. The power duster used is shown in Figure 16. 



Fig. 12.— Spraying beans for the Mexican bean beetle with a power sprayer. This machine may 

 be adapted to spray 8 rows at once. 



EXPLANATION OF TABLES. 



Table 9 gives only the results of the experiments performed with 

 the arsenicals commercially available, arranged by experiments 

 chronologically. Table 12 gives results of dusting experiments, 



