74 



ABC OF THE STEEL SQUARE 



arranged on the iron square, then measure across 

 the angle from the points of run and pitch, and 

 multiply this measurement by half the width of 

 the roof to be covered." Now this is all right, 

 but, as a matter of fact, entails more labor of 

 a "tiresome sort" and would use much more time 

 than the method I have taught now for nearly 

 forty years. The American workman, however, 

 does not even require a suggestion as to the 

 quicker method. He will see and adopt it at 

 once without argument. 



Fig. 



The method the Englishman would adopt is 

 shown at Fig. 48, where the points of pitch 

 and run are shown at IS and 8, which makes the 

 diagonal line 14% inches. To get the length 

 of the rafter for our supposed building then, 

 we must multiply this 14% inches fifteen times, 

 then we must use the square at the top and bot* 



