736 



IOWA DEPARTMENT OF AGRICULTURE. 



depths. These estimates apply to silos filled with well matured corn 

 that has been allowed to settle forty-eight hours and then refilled. It 

 is evident Lhat to get this rated capacity a silo which had been filled 

 rapidly must be refilled after settling forty-eight hours. 



Table 1. Approximate Capacity in Tons of Cylindrical Silos of Dif- 

 ferent Diameters and Depths. Computed Feoji King's T.\ble. 



(The diameter is shown at the top of columns and depth at the left) 



INSIDE DIAMETER IN FEET. 



ROUND WOOD SILO PLASTERED WITH CEMENT. 



The silo described below, which is 20 feet in diameter and 341/^ feet 

 deep, having a capacity of 228 tons, was built at the University of 

 Illinois the summer of 1903. The first silos of this kind built in the 

 state, so far as known by the writer, were three erected by Mr. H. B. 

 Gurler of De Kalb in 1897. (This is the style of construction frequently 

 referred to as the Gurler silo.) These three silos have been filled every 

 year and have given most excellent satisfaction. It seems probable that 

 silos of this construction will not only preserve the silage perfectly but 

 will prove to be lasting as well as economical. As few silos of this type 

 have as yet been built in Illinois, a detailed description of the one at 

 the University is given. 



The excavation and foundation were made by cutting a circle 20 

 feet 10 inches in diameter and four feet deep, and laying up a four- 

 inch brick wall against the clay. (Cut 12.) This wall was slushed 

 in full on the back side with mortar so that every brick had a full bear- 



