REINFORCED CONCRETE. 125 



will cause it to settle unevenly, in which event the walls 

 are liable to crack and so admit air; consequently, spoiled 

 silage will be the result. 



The Missouri State Board of Agriculture in its March, 

 1906, bulletin describes a concrete silo built by Mr. C. J. 

 W. Jones, Roanoke, Mo., in the summer of 1905, as follows: 

 "It is 16 by 40 feet inside measurement, it being 9 feet in 

 the ground. He first dug the hole and leveled the bottom. 

 Then started the inside form, which was made of old 

 pieces of fence boards stood on end around the circle and 

 held in place by thin limber boards tacked onto them. He 

 also had a center pole to guide by and brace to. The bot- 

 tom wall was made thick and tamped against the earth 

 bank. When the level of the ground was reached he care- 

 fully leveled up the work and started the outside form, 

 which was made of a band of iron, 20 inches wide and 

 53.43 feet long, rolled to form the circle and was fastened 

 with clamps at the ends. The silo being 16 feet in diame- 

 ter and the walls 6 inches thick, the form is then 17 feet 

 in diameter. This was leveled and the space between it 

 and the inner wall of boards filled with concrete and 

 tamped. When this hardened the form was loosened, 

 raised and screwed tight again after getting it level; the 

 space again filled and so on to the top. The inner wall 

 was raised as needed, being braced against the center 

 pole from all sides." 



The wall was reinforced to prevent cracking by build- 

 ing a wire rope into it every few feet. The door frames 

 were built into the wall while it was being made. The 

 material for the silo cost about $150.00. 



We quote from Bulletin No. 125 of the Wisconsin 

 station: 



"A common type of form used in making a continuous 

 wall or monolithic structure is illustrated in Fig. 41. A is 

 the outside form and B the inside form. These forms are 

 made as segments of the circle 6 or 10 feet in length and 

 1% to 3 feet deep. A form is made by taking two pieces 

 of plank 2x12 or 2x14, LL and UU, Fig. 41 A, sawing them 



