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Illinois State Dairymen's Association. 



We expect to investigate the subject of concrete silos during 

 the coming year and erect one or two small ones of this construc- 

 tion at the University. 



Brick Silos. 

 Where brick is cheap and stone and gravel scarce, a brick 

 silo may be the most economical. In large brick silos the wall is 

 usually built with three or four courses of brick at the base and 

 made a course thinner at various heights until reaching the upper 

 ten feet, which need not be more than eight inches thick. Cut 29 

 shows a brick silo built on this plan. This silo rests upon a 

 seven-foot stone foundation 18 inches thick; six feet of it being 

 below the ground. Upon this are laid three courses of brick, the 

 middle course being of brick tile which contains a dead-air space, 

 and thus prevents freezing to a great extent. This wall extends 

 twelve feet above the foundation, and from that point to the top 

 two courses of brick are used with one and a half inch air space 

 between. One silo 16 feet in diameter and 30 feet deep, built in 

 this manner, holds 120 tons and cost $250, or $2.08 per ton. An- 

 other silo of the same depth and 19 feet in diameter holds 168 

 tons and cost $350, or $2.08 per ton, the same as the smaller silo. 



stone Silos. 



Where stone can be easily and cheaply obtained silos may be 

 built of this material. Cut 30 shows a stone silo which is 18 feet 

 10 inches in diameter and 30 feet deep, holding 156 tons. The 

 wall of this silo is two feet thick and extends five feet into the 

 ground. The portion below the surface is made of hardheads, 

 while that above is of quarry stone obtained from a neighboring 

 farm. The inside is plastered with Portland cement. The first 

 door is 2x6 feet, the next 2x3 and the upper 2x4 feet. This silo 

 cost $500 besides the labor of the owner, which amounted to 

 about $100, making the total cost $600, or $3.64 per ton capacity. 

 Although the material may be cheap and close at hand, the ex- 

 pense of elevating heavy stone for so thick a wall, and the employ- 

 ment of a stone mason, which is high priced labor, make a stone 

 silo expensive. 



The silo shown in Cut 31 is 20 feet in diameter and 32 feet 

 deep, having a capacity of 204 tons. This silo extends eight feet 

 into the ground, which is too deep, requiring extra labor in re- 

 moving the silage. The wall of the lower 12 feet is 24 inches 



