STUMP-PULLERS, DERRICKS, SLINGS. 



147 



DERRICKS FOR FARM USE. 



Where there is much handling of heavy barrels or 

 sacks, one man, with some simple, mechanical contriv- 

 ance, can easily do the work of two or three, working bv 

 main strength. A boom derrick, figure 178, hung high, 

 so that the weight shall be lifted from the ground ordi- 

 narily, when the derrick swings horizontally, is very con- 

 venient. A post is banded, and has a strong dowel at 

 each end. The lower dowel is set in a stone fixed in the 

 ground, close to the building where it is to be used, the 



Fig. 178. A BOOM DEREICK. 



Fig. 179. EYE-BOLT. 



upper one in a strong oak cleat, bolted to the building. 

 At the height of about five or six feet from the ground, 

 an eye-bolt passes through the post, and another is fixed 

 at the top. The boom is fastened to the lower eye-bolt 

 by a three-quarter inch hooked iron, attached a-s shown 

 in figure 179, while the other end of the boom has a band 

 with two eyes. This boom is a spar or pole, stiff enough 

 to bear the strain without doubling up or breaking, and 

 may be ten or fifteen feet long. The end of the boom is 

 raised or lowered by a pair of single pulleys, or by a 



