A B C OF THE STEEL SQUARE 81 



Better still, however, would have been the appli- 

 cation of the square 15 times on the edge of the 

 rafter pattern with the points 12 and 6 on 

 gauge points, then both length and bevels would 

 have been obtained at one operation. 



Of course, the expert workman will often in- 

 vent, or discover, methods of using the square 

 in certain phases of roof framing, that can not 

 be found in books, or that cannot be taught 

 because of the peculiar circumstances of the par- 

 ticular case. Having a fair knowledge of the 

 uses of the steel, the workman will seldom be 

 overtaken by difficulties he cannot overcome if 

 he studies the problems before him and then 

 employs his knowledge of the square to their 

 solution, as a little application on this line will 

 remove all possible troubles. 



Every carpenter knows, or ought to know> 

 that the run and rise of the rafter taken on the 

 square will give the seat and plumb cuts, but 

 inasmuch as buildings are not all of the same 

 width, it requires a different set of figures for 

 each run, and as it requires an extra calcula- 

 tion to first find the run of the hip or valley, it 

 is better to use the full scale for a one-foot run 

 of the common rafter which answers for any run. 



Referring to Fig. 51, we show a square 

 bounded by A, B, C, D, the sides of which are 



