FARM STRUCTURE 



469 



Monolithic Silos. The solid wall does not offer serious 

 objections in permitting the freezing of the silage, especially 

 if provided with a good, 

 tight roof. The concrete 

 silo blocks are nearly al- 

 ways made to contain an 

 air space, and double forms 

 may be used in the mon- 

 olithic construction, mak- 

 ing a double wall. When 

 air circulation is restricted 

 in the dead-air space by 

 horizontal partitions about 

 every three feet of height, 

 the double wall is perhaps 

 the most satisfactory, as 

 far as frost-proof qualities 

 are concerned. 



The cost of a concrete 

 silo will depend largely 

 upon local conditions. The Fi s. 295. a 

 cost of sand, gravel, and 

 labor are the deciding factors. Under usual conditions, the 

 cost should not greatly exceed the cost of a first-class wood- 

 en silo. No attempt will be made here to discuss the con- 

 struction of forms. 



The Hollow Clay Block, or Iowa Silo. In general, this 

 silo consists of a wall of vitrified clay building blocks reinforced 

 with steel laid in the mortar joints. The roof is made of 

 concrete, and the silo has a reinforced concrete door frame. 



Description of the Blocks. The blocks are hard-burned 

 building blocks, and may now be had curved to the curvature 

 of the silo wall, making a smoother wall on the inside. These 



monolithic silo with con- 

 crete roof. 



