PRODUCTION OF SWEET-ORANGE OIL. 
15 
The grating surface of the drum is made of No. 24 galvanized iron, 
cut into strips 4 inches wide and punched to form the special teeth 
required. These teeth are formed by a triangular punch with two 
sides straight and the third beveled to form the point. The punch 
should be adjusted so that when used on a lead block a triangular 
tooth will be cut, having one point exposed. The teeth are from 
three-sixteenths to one-fourth of an inch long, with the point raised 
from three thirty-seconds to one-eighth of an inch. They are about 
Perspective view of the peeling machine. 
three-fourths of an inch apart each way and so placed that when the 
strips are in position on the drum the teeth will project in the direc- 
tion in which the drum rotates. It is essential that the point and 
edges of the punch be kept sharp, in order to make a clean-cut tooth 
having a sharp point. It is desirable to mark off the strips on the 
sheet of galvanized iron and punch the teeth before cutting the 
strip, leaving a margin of at least one-half an inch on each edge. 
This prevents the strips from being warped out of shape in the punch- 
ing process. 
