PRACTICAL SILO CONSTRUCTION 47 



For the door-openings a double length block is 

 constructed, as shown in illustration. This should 

 be of the proper curve to conform to the circumfer- 

 ence of circle, and also be reinforced with at least 

 three " rods placed horizontally in same. Two of 

 these rods are placed within about 1 " of the bottom of 

 block, which forms the upper part of the door-frame ; 

 the third rod is placed about 3" above this, and may 

 be further strengthened by short stirrup rods con- 

 necting the horizontal reinforcement. The door- 

 frames may be set in position as the blocks are 

 placed; and, by attaching to the reinforcement of 

 the silo, the frames are thus held rigidly in posi- 

 tion against the pressure of the silage. 



At Fig. 11 is shown a plan of laying the silo 

 blocks so as to make a continuous door-opening from 

 top to bottom of the silo. The blocks are molded or 

 cut at the point they intersect at the door-opening 

 so as to lock in the manner shown. This can be accom- 

 plished by using a block of wood set vertical in one 

 end of the mold used for these blocks, and thus saving 

 the labor of cutting each block to join in this manner. 



The reinforcing wires are bent to form a contin- 

 uous reinforcement or bond to the end of the door- 

 opening. 



In constructing the blocks for a known size or 

 diameter of silo it is an easy matter to make them 

 of a length so that it requires a certain number of 

 blocks to make the exact circumference. Then, by 

 molding a number of half blocks, the joints may be 



