THE CONSTRUCTION OF MODERN SILOS 781 



hinged to the frame, or they may simply be put in place while chap. 

 the silo is being filled, and suspended with chains to the wall XVL 

 when not in use ; the former method being perhaps the more 

 satisfactory. To make the doors more perfectly air-tight, thick 

 felting is sometimes tacked to the frame, and stout paper is 

 often pasted over the doors for the same purpose. 



75 5. Chute. — In most cases it will be found of great ad- 

 vantage to have a vertical chute attached to the silo, down 

 which the silage can fall when emptied from any of the doors. 

 It is made in the form of a long box, extending from near the 

 ground to the top of the silo, and covering the doors. It 

 requires only three sides, the wall of the silo forming the fourth, 

 and should measure about 2 feet 6 inches by 2 feet inside. A 

 ladder running up the full height is fixed inside the chute, 

 giving access to the doors when the silo is being filled or 

 emptied. The lower end may be left open or may be fitted 

 with a sloping bottom to slide the silage into a cart, barrow, 

 or other receptacle used for conveying it to the cattle. A 

 small door can be formed in the front or side to give access to 

 the ladder. 



The accompanying diagram (Fig. 244) shows a square silo 

 measuring 1 7 feet each way on plan and 25 feet in height (above 

 ground) and having a capacity of 4,900 cubic feet, equal approxi- 

 mately to 98 tons of silage. It is on the lines described in the 

 preceding paragraphs, built of stone in lime mortar, covered with 

 a roof of corrugated iron, and having a floor of cement concrete 5 

 feet below the ground level. Four emptying doors are shown 

 on one side and a filling door in the roof. There is a triangu- 

 lar ventilating panel over the filling door and a large ventilator 

 at the apex for escape of foul air, and for the admission of 

 fresh air there is an opening of about 4 inches high between 

 the walls and the roof all round. The inside corners are 

 shown well rounded to facilitate the settling of the silage. 

 Though shown standing alone, it need not necessarily do so, 

 but could be attached to other buildings where found most 

 convenient. 



Such a building, if erected by contract at current prices in 

 South Africa, would cost approximately £230, but a farmer 

 could build it much more cheaply by employing local trades- 

 men and providing all necessary transport and native labour. 



