202 



FARM MECHANICS 



the size of pulleys and the speed of intermediate shafts 

 between his engine and the machine to be driven. A 

 speed indicator is held against the end of a shaft at 

 the center. The indicator pin then revolves with the 





Figure 182. Speed Timers. Two styles. The point is held against 

 the center of the shaft to be tested. The number of revolutions per 

 minute is shown in figures on the face of the dial. The indicator 

 is timed to the second hand of a watch. 



shaft and the number of revolutions per minute are 

 counted by timing the pointer on the dial with the sec- 

 ond hand of a watch. 



Figure 183. Building Bracket. Made of 2x4 pieces put together 

 at right angles with diagonal braces. The supporting leg fits be- 

 tween the four diagonal braces. 



SOIL TOOLS 



Soil moisture often is the limiting factor in crop 

 raising. Soil moisture may be measured by analysis. 



