102 



F HIM MECHANICS 



Figure 115. The Farm Pump. It superseded the iron-bound 

 bucket, the slimy old bucket, the malaria-lined bucket that hung 

 in the well, but it wore out the women. Oil was never wasted on its 

 creaking joints. Later it was fitted with a stuffing-box and an air- 

 chamber, and the plunger was hitched to the windmill. 



To the right are shown two kinds of post-hole diggers. The upper 

 digger is sometimes used to clear the fine earth out of the bottom 

 of a hole dug by the lower digger. 



to do with the flow of water. When water is forced 

 through a small pipe at considerable velocity, there is a 

 good deal of friction. Often thje amount of water de- 



