lo Aug., 191 1.] 



Silo Construction. 



567 



vertical joints with spun-yarn j put in all the bolts and tigjiten up. 

 Securely fix the sections to stumps with dog spikes. 



Xow take one of the long lengths of roof timber, attach block and 

 tackle to end, set up against a vertical joint and fasten. This is to 

 be used for hoisting the top sections into position. Bolt horizontal joints 

 loosely, breaking the vertical joint. It will be necessary to shift the up- 

 right timber as each section is placed in position. Do not tighten any 

 of the joints till spun yarn has been packed in. After packing all joints 

 screw up all bolts tightly ; then put the stiffening plates on top of silo. 



Roof.- — The ridge of the roof .should run in a line with the elevator, 

 which is fixed under the gable. The ridge and intermediate purlins are 

 .•supported on six stanchions bolted to the top of the silo. Each stanchion 



ALL-STEEL SILO —SECTIONS. 



Js made of two angle irons riveted together and spread out at foot 13 in. 

 The flanges are cut away for 4 in. down from top and holed for | in. 

 bolts. The foot is drilled for two | in. bolts to correspond with holes in 

 angle iron at top of silo. The two stanchions for ridge purlins are 3 ft. 

 high, the other stanchions 2 ft. high. Bolt on the two longest stanchions 

 opposite one another to carry the ridge purlins, to which they are bolted. 

 Allow the ends to project 2 ft. over each side of silo. This is to permit 

 the use of block and tackle for hoisting. Bolt the outside purlins to top of 

 silo, keeping them parallel with the ridge and 6 in. from inner face ct 

 wall. With the aid pf a straight-edge and square set off so that the ends 

 of these purlins are on a line with a mark made 9 in. in from end of ridge 

 purlins. With the straight-edge, get i)itch of roof and bolt on the remain- 

 ing stonchions to take the intermediate purlins. Cover the purlins with 

 •9-ft. sheets of corrugated iron, allowing a lap of one and a half corruga- 

 tions. Secure with 2i-in. spring-head nails at every third corrugation. 

 Fix three lengths of t6 in. ridging with 2^ -in >]>ring-hcad nails everv 

 2 ft. 



