PRACTICAL SILO CONSTRUCTION 4& 



the form constructed to make a bottom for the en- 

 tire length of the mold. 



The sheet iron dividing plates are cut in the con- 

 vex and concave form shown in Fig. 9, at top. The 

 length is equal to the length of the block, plus 4 " at 

 each end for inserting in the saw kerf and for a hole 

 in the ends for putting an iron pin into, to hold the 

 side forms or planks tightly up against the " shoul- 

 der" cut upon the dividing plate. 



A beveled or triangular strip of wood is now cut 

 of the exact length of the block. This, by soaking 

 in water, can be bent to the curve of the block, and 

 is then nailed to the top of the dividing plate, or 

 about li " from the top, as shown in the illustration 

 at Fig. 9. This molds a groove in the silo block for 

 the placing of the hoops or wires used as reinforcing 

 material. This groove is shown in the completed 

 block at Fig. 9. 



Below the triangular strip, round holes are cut 

 for inserting lengths of gas-pipe, which mold the 

 hollow spaces in the blocks. These pipes are well 

 greased when the mold is assembled and also slightly 

 flattened at one end, into which a key or crank is 

 placed for turning the pipe around before removing 

 same from the completed series of blocks. This is 

 necessary, as otherwise the pipes could not be as 

 easily drawn; but, by breaking the bond, if any, be- 

 tween the pipes and concrete, they are withdrawn 

 quite easily. 



Two of the dividing plates are used between each 



