A B C OF THE STEEL SQUARE 



25 



the run, rise and pitch of rafters, being spe- 

 cially figured for this purpose, and shows the 

 measure of the rafter for any one of seven 

 pitches of roof based upon the length of the 

 horizontal measurement of the building from 

 the center to the outside. 



The following table, which was prepared es- 

 pecially for this square, shows the manner of 

 working the square: 



Fig. 10. 

 RAFTER TABLE DIRECTIONS. 



The rafter table and the outside edge of the 

 back of the square, both on body and tongue, 

 are in twelfths. The inch marks may represent 

 inches or feet, and the twelfth marks may rep- 

 resent twelfths of an inch or twelfths of a foot 

 (that is, inches) as a scale. The rafter table is 

 used in connection with the marks and figures 

 on the outside edge of the square. 



