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case of silos of large diameter, when the edges are best sized square. Staves 

 with a tongue and shallow groove are more easily kept in place. Great care 

 must be taken to have the lumber well sized and free from knots or shaky 

 spots. 



(Fig. 10.) Stave with tongue and groove. 



After the staves are squared at the ends, holes should be bored in the 

 edges, from 4 to 6 feet apart, with a %-inch bit, on one side of each stave 

 only, and not in line in adjoining staves. They should be of the depth of 

 1 inch in staves, 4 inches wide, and about 2y% inches deep in staves 6 inches 

 wide. One of these holes should come within a foot or less of each end of 

 the stave. Bore the holes at right angles to the edge of the stave to avoid 

 throwing the silo out of plumb. Spikes are driven through the holes into the 

 adjoining., stave. Avoid those portions of staves to be cut out for doors. 



SPLICING. 



It will often be necessary to make the staves of two different pieces. 

 The ends should be carefully squared, and by making a saw-cut an inch or 

 so deep, and inserting a bit of heavy hoop-iron, a good splice is secured. 

 Break the joints alternately towards the top and bottom of the silo. 



(Fig. 11.) Spiking staves together. 



(Fig. 12.) Splicing stave. 



THE DOOR-STAVE. 



Before beginning the erection of the staves, decide how many doors the 

 silo needs, that a door-stave may be prepared. When the number of doors 





(Fig. 13.) The door-stave. 



