1911.] PUBLIC DOCUMENT — No. 31. 51 



cylinders, which, on account of the wciiiht, niust have a limited 

 capacity for storing the air. There are on the market many 

 good hand pnnips which will maintain a pressure of 50 to 70 

 pounds with an ordinary nozzle, and these may be purchased for 

 $U2 to $20. For general purposes they are the cheapest and 

 most satisfactory spraying devices produced at the jiresent time. 



