86 HOW TO BUILD A SILO. 



Specifications for 100-ton Silo. 



MASONRY. 



Excavate the entire area to be occupied by the silo to 

 a depth of six inches; excavate for foundation wall to a 

 depth of 16 inches; in this trench build a wall 18 inches 

 wide and 20 inches high, of field stone laid in rich lime 

 mortar. Level off top and plaster inside, outside and on 

 top with cement mortar, 1 part cement to 1 part sand. 

 Fill inside area with four inches of good gravel, thoroughly 

 tamped down; after the wood work is in place coat this 

 with one inch of cement mortar, 1 part cement to 1 part 

 clean sand. Cement shall be smoothly finished, dished 

 well to the center and brought up at least 2 inches all 

 around inside and outside walls. 



CARPENTRY. 



All staves shall be 26 feet long in two pieces, breaking 

 joints, and made from clear, straight-grained cypress, 2x6 

 inches, beveled on edges to an outside radius of 8 feet, 

 mill-sized to the exact dimensions and dressed on all sides. 

 There shall be three doors in the fifth, eighth and tenth 

 spaces between the hoops, made by cutting out from staves 

 28 inches long cut to a 45-degree bevel sloping to the 

 inside. (See Fig. 13.) The staves shall then be fastened 

 together with two 2x4-inch battens cut on inside to an 

 8-ft. radius and bolted to each stave with two ^-inch 

 diameter carriage bolts with round head sunk on inside 

 and nut on outside. The staves between the doors shall 

 be fastened together, top and bottom, with ^-inch diam- 

 eter hardwood dowel pins, and abutting ends of staves 

 shall be squared and toe-nailed together. 



Bottom Plates. Bottom plates shall be made of 2x4- 

 inch pieces about 2 feet long, cut to a curve of 7 feet 10 

 inches radius outside. They shall be bedded in cement 

 mortar and the staves shall then be set on the foundation 

 and well spiked to these plates. 



