EXPERIMENT STATION BULLETINS. 237 



The roof is carried by 2x4 rafters, set 24 inches apart, center to 

 center, on the plate, and converging to the center, or peak. Short 

 pieces of 2x4 are nailed at intervals from plate to peak and at right 

 angles to the rafters to carry the sheeting. The sheeting is set at right 

 angles to the plate; otherwise the sheeting and shingling does not 

 differ from that of other roofs. 



A dormer window, facing the south, was originally used for ventila- 

 tion and to admit the cut corn and other material to be ensiled. The 

 enclosing of the silo by other buildings recently has made it necessary 

 to cut a hole in the west side just under the eaves to admit cut material. 



The doorway is cased with a single Yg inch piece placed flush with 

 the inner edge of the stud and extending out just beyond the outer 

 surface of the siding, which is laid against it. This piece acts as both 

 jamb and stop. 



The doors consist of y^ inch boards placed against the jambs and 

 uncovered portion of the stud, after the manner of placing bin board in 

 our granaries. As the filling progresses the boards are set in place, 

 and against these are tacked 34-inch strips of number 28 galvanized 

 sheet iron, which overlap each other by about an inch and reach about 

 four inches beyond the edges of the doors. 



In this silo we have kept silage to the third season. 



For ventilation between the walls of this silo an inch hole was bored 

 into each space between studs (1) through the outer wall near the 

 sill, and also (2) through the false plate separating the lower from the 

 upper tier of studs. It has never proved satisfactory. 



The question of the desirability of basswood for silo lining or sheet- 

 ing should be considered at this point. This silo has been built seven 

 years. In the upper two-thirds of the wall the basswood sheeting is 

 apparently, at this time, in a good state of preservation; but in the 

 lower portions of the wall where the silage has remained in contact 

 with the wall well into or even through the summer, a good deal of 

 rotting has occurred. Indeed, near the sill, several pieces of sheeting 

 have had to be replaced. 



The other all-wood silo. Fig. 26, was constructed in 1897. In the 

 fall of 1904 it was moved some 300 feet and placed upon a new founda- 

 tion. 



This silo has an inside diameter of 18 I/2 feet, and a height of 261/2 

 feet above the foundation upon which it rests. The foundation in turn 

 has a height of 6 feet above the silo floor, thus making the total height 

 of the silo about 32 feet. The top of the foundation wall stands about 

 12 inches above the ground. 



The capacity of the silo is 130 to 150 tons, depending upon the man- 

 ner of filling. 



In a few particulars this silo differs in construction from our other 

 all-wood silo. 



The studs stand 12 inches apart, center to center, as in the other; but 

 the pieces of each stud, 12 feet and 14 feet in length respectively, are 

 placed end to end and spliced by nailing on each side of the joint a 

 three foot strip of 2x4. A strip of 1x4 would have answered just as 

 well. In setting up the studs, the alternate ones had their 14 foot ends 

 set downward. 



