158 



Concrete Silos 



These holes are 2 feet apart and 2 inches from the edge. 

 The pieces are then ripped through the holes. A piece 

 of 2x2 inch lumber, beveled, is then nailed to the 4-inch 

 piece thus made. Cleats are nailed across the two pieces 

 which were cut. These cleats are to hold cross-strips 

 between the two uprights, for the purpose of keeping 

 the door forms the right distance apart. 



2x2' 



2x6' 



Form for Intermittent Doorway. 



When setting the form into the molds, the ladder or 

 door rods are placed in the holes of the door form. This 

 method of door-jamb construction has been in use for 

 eight or ten years, and has been found satisfactory. 

 The method of reinforcing across both types of door 

 openings is also shown herewith. 



Doors. The doors for the continuous doorway may 

 be made of 2-inch planking, preferably tongue-and- 

 grooved. The doors should be 34 inches in width and 

 30 inches in height. Five pieces of planking 6 inches 

 wide, or 4 pieces 8 inches wide may be used con- 

 veniently. A %-inch hole is drilled on the vertical 



