116 A B C OF THE STEEL SQUARE 



been done is that the plane in which the rail lies 

 has been projected to intersect the horizontal 

 plane which contains the plan of the wreath. 

 The name by which this line is generally known 

 is the horizontal trace (shown at C, Figs. 78 

 and 79). The minor axis (Figs. 78 and 79) is 



Fig. 79. 



always parallel off this, and always touches A 

 as in Fig. 77. The major axis (Figs. 78 and 

 79) also touches this point A, and is always 

 square off the minor axis and off the horizontal 

 trace. It will be seen by this that the rail is 

 pitched equally both ways; therefore the face 

 mold will be of equal width at the ends. 



