Construction of Stone Silos. 



399 



496. Doors. Doors for filling and feeding should be ar- 

 ranged as represented in A, Fig. 196, and if the lower one 

 is long, cutting out a good deal of the wall, an iron rod 

 should be bedded in the wall above it to prevent cracking 

 between the doors. The rod should be of f inch round iron 

 bent to the curve of the circle and about 12 feet long. The 

 two ends should be turned short at right angles, so as to 

 anchor better in the mortar. 



In deep stone silos, which rise more than 18 feet above 

 the surface of the ground, it will be safest to strengthen the 

 wall between the two lower doors with iron tie rods and, if 

 such a silo is built of boulders, it will be well to use rods 

 enough to make a complete line or hoop around the silo 

 about two feet above the ground, as represented in Fig. 

 198. 



Fio. 198. Showing method of bedding iron rods in stone, brick or con- 

 crete silo walls to increase the strength. The heavy lines with ends 

 bent represent the iron rods. 



The door jambs for the stone silo are best made of 4x4's 

 framed together and set far enough apart to give a depth 

 four inches less than the thickness of the wall. This will 

 allow mortar to be filled in between the 4x4's to make an 



