Concrete Silos 



153 



bound together with four ^-inch galvanized iron 

 rods, 8 inches long and turned 1 inch at each 

 end. The Standard 

 Anchor machine 

 makes a block 8x8x 

 24 inches, while the 

 Junior Anchor ma- 

 chine makes a block 

 8x8x16 inches. Each 

 machine makes 

 blocks to fit any de- 

 sired radius of silo. 

 This is accomplished 

 by having the mold 

 box equipped with 

 inside steel plates 

 which can be ad- 

 justed by set screws 

 to the desired curve. 

 The interior section 

 of the block is cast 

 with a groove in the 

 top in which rein- 

 forcing can be 



placed. Anchor Blocks Laid Up in Wail 



Keystone Cement Slab Silo. This system is con- 

 trolled by the Minnesota Keystone Silo Company, Min- 

 neapolis, Minn. The blocks or slabs used in a Key- 

 stone silo have a special design, the ends being wider 

 by 3 inches than the center of the slab. This, in addi- 

 tion to the tongue-and-groove edges, makes of each 

 block a key which securely locks the adjoining slabs. 

 The slabs or blocks are 24 inches long, 3 inches thick, 



