THE IOWA SILO 83 



boards, H, which are placed 22 inches apart. The boards, H, 

 should be beveled on the edge J4 mc h m two inches, to con- 

 form to the curvature of the inner side of the silo wall. The 

 edges need not be beveled thinner than % inch. The bev- 

 eled strips, 7, are nailed to the end flush with the inner edge 

 of H. Only a bevel of ^g inch is necessary here, as the lum- 

 ber of the door extends horizontally, therefore there is little 

 or no shrinking or swelling of the lumber in this direction. 

 Holes must be bored in G to receive the bolts which hold the 

 two parts of the form together. The cost of these forms need 

 not exceed $12. 



