288 ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 



14 feet in diameter $ 9.00 per foot of height 

 16 feet in diameter 10.00 per foot of height 

 18 feet in diameter 11.50 per foot of height 



Double Wall Silos : 



14 feet in diameter $13.00 per foot of height 

 16 feet in diameter 14.00 per foot of height 

 18 feet in diameter 16.00 per foot of height 



Many excellent stone silos were found in Wisconsin giving 

 the best of satisfaction. They are especially attractive in ap- 

 pearance and there is no doubt about their reliability when plas- 

 tered so as to make the walls air and water tight. They are 

 about as frost proof as single wall brick and concrete silos. The 

 walls, however, are thicker, ranging from 16 to 24 inches, de- 

 pending largely upon the kind of stone. It is best that only 

 cement mortar be used. The walls should be reinforced by 

 building steel bands into the wall. The cost of the stone silo 

 will depend altogether upon the availability of the stone. 



Clay Pipe Silos. 



The clay pipe silo is constructed of interlocking clay pipes 

 or tiles. Several of these silos were visited and found to be 

 giving good satisfaction. The clay tube is similar to a five inch 

 drain tile except that the walls are heavier and slotted at four 

 points 90 degrees apart to a depth of one-fourth its length. The 

 tubes are set on end with the slots interlocking. Steel bands or 

 hoops are placed around the wall and then plastered smooth with 

 cement plaster. This type of silo up to the present time has been 

 rather expensive. 



The Iowa Silo. 



The Iowa silo is a new type of silo with walls constructed 

 of common rectangular building tile. As far as known to the 

 writers at the time the first edition of this bulletin was pre- 

 pared, silos had not up to that time been constructed of this ma- 

 terial. A thorough investigation of the matter left but little 

 doubt in regard to the reliability, adaptability, and cheapness of 



