SIXTH ANNUAL YEAR BOOK — PART VIII. 



751 



the next 14 feet, and 16 inches thick the upper 14 feet. This silo cost 

 approximately $1200, and as it holds 334 tons, the cost per ton was $3.59. 

 While the first cost of this silo was high it may prove economical in 

 the end as* it should stand for more than a hundred years. 

 ■ It is essential that a concrete, stone, or brick silo have a good 

 foundation, otherwise it is likely to settle unevenly and cracks will 

 appear in the wall, giving the air a chance to enter. If the silo is put 

 at least three feet into the ground this assures a firm footing and also 

 adds to the depth of the structure. 



There are great possibilities in reinforced concrete and a circular 

 structure is the best to be easily reinforced. Silos have been built of 

 concrete but usually with solid walls and much thicker than necessary. 



Cut 30.-Stone Silo 18 feet 10 inches in diameter and 30 feet deep; capacity 156 tons^ 



Cost about $600.. 



