Spraying for the Alfalfa Weevil. 15 
in the pressure line beyond the cut-off (fig. 8). ~-A 14-inch T is used 
as the shell, and the pipe from the pump is screwed into its middle 
opening. The T is turned so that the other two openings point up 
and down and a plug is screwed into the lower opening whence it 
can be removed to clean out the strainer. The strainer itself is a cone 
of 20-mesh brass or bronze screen strengthened by crossed hoops of 
No. 14 galvanized wire, both soldered to the inside of a 14 by 1} inch 
bushing, which is then screwed into the upper opening of the large 
T so that the cone points down into the T. This bushing is connected 
by suitable bushings with the hose leading to the boom. The spray 
Fic. 8.— Pressure strainer attached to spray outfit. 
liquid from the pump enters the shell at the side opening and flows 
upward through the screen cone and out at the top toward the nozzles, 
leaving the dirt on the outer lower side of the cone, from which it 
can be removed after taking out the bottom plug (fig. 9). 
THE ENGINE. 
The capacity of the gas engine should be about 1 horsepower for 
each. gallons per minute pump capacity. The power is transmitted 
to the pump through a jack, driven by a belt or gears, which should 
give a gear reduction of about 10 to 1. Some spray pumps are built 
with a crank shaft or eccentric shaft, which takes the place of the 
jack. 
