58 



ENGINEERING ON THE FARM 



The lower block A in Figure 87 is a single block without 

 a becket. 



Reeving blocks. Reeving blocks is the process of pass- 

 ing the rope through the blocks in the proper way so as to 

 get them ready for use. In any set of blocks one of them 

 has a becket to which one end of the rope must be fastened. 

 If both blocks have the same number of sheaves, the one 

 having the becket is the fall-block. If one block has one 

 sheave less than the other, the becket must be on the block 

 with the smallest number of sheaves, but the other is the 

 fall-block. 



In reeving blocks by the directions which follow, the rope 

 is passed through the blocks in the direction opposite to 



that in which it runs when 

 the blocks are being used 

 to lift or pull. This is to 

 avoid the necessity of pull- 

 ing all the rope through 

 the blocks in order to get 

 them reeved. 



A set of blocks in which 

 both blocks have the same 

 number of sheaves is reeved 

 in the following way: 



1. Start with the block 

 having the becket, the fall- 

 block, by passing the rope 

 over the sheave which is 

 farthest from the becket as 

 shown in Figure 83. If the 

 becket is in the middle, the 

 ope may be passed over 

 either outside sheave. 



Fig. 85 



Fig. 86 



2. Pass the rope over the proper outside sheave in the 

 other block and then over the next sheave in the block, 



