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SILOS: CONSTRUCTION AND SERVICE 



able that the guide be simple, easily used, and in the way as 

 little as possible when not in use. A common board about 6 

 feet long and cut to proper curvature also aids in getting a 

 good, smooth, round wall. It is of course possible to build 

 a circular wall by starting the circle, then using the plumb at 

 intervals on the wall. However, the guide devised has been 



Nail to scaffold 

 LTVumb line. 



GUIDE. 



for laying wall plumb and to true circle. 

 Fig. 21. A guide device used in constructing the wall. 



found better for this purpose by men who have tried both 

 ways. It is also advantageous, since, by means of ifc, the 

 owner of the silo may in a very few minutes detect any 

 faulty shape of wall. It is merely necessary to determine the 

 proper position of the center-pipe by means of the plumb-bob; 



