126 



ABC OF THE STEEL SQUARu 



blade and 10 on the tongue of the square anc 

 measuring across, giving the length of the side 

 rafter, from which one-half the thickness of tin 

 ridge, measured square back from the pluml 

 cut, must be deducted. The blade gives the fpo* 



cut and the tongue the plumb cut. The length 

 of the end rafter is obtained by taking 16 on 

 the blade and 10 on the tongue, which will of 

 course give the respective cuts also. The same 

 results may be obtained by applying the squarf 



