422 



APPLIED SCIENCE 



FIG. 200. 

 Looking 

 Down 

 Edge of 

 Cross-Cut 

 Saw (En- 

 1 a r g e d 

 View). 



deeper and deeper, gradually bringing into action 

 the cutting edge on the outside front of the points 

 of the saw. The forward motion of the saw blade 

 causes the points and cutting edges to strike the 

 fibers of the wood at a right angle to their length, 

 thus separating them from the main body of wood 

 on each side of the blade. A continuation of the 

 pressure or thrust carries the teeth in farther and 

 farther, until the full "bite" is taken. The saw 

 points are continually scoring the wood on each 

 stroke. The outside edges of the saw part the 

 fibers, and the beveled front edge of each tooth 

 in the cut acts like a chisel in crumbling and dis- 

 lodging the upper portion of the ridge of wood left 

 between the cutters. The pieces of wood are 

 carried out of the kerf by the throats or gullets at 

 each thrust of the saw, until the board is com- 

 pletely cut. 



486. How to Handle a Saw. A carpenter 

 should use his hand-tools so as to obtain the 

 greatest results with the least effort, and in this 

 manner conserve his energy. The saw should be 

 grasped by the handle with the thumb and fore- 

 finger extended, so that the handle fits in the 

 hollow of the hand and gives an easy "hang" to 

 the saw. It should be guided by the left thumb 

 knuckle pressing against the blade. This move- 

 ment keeps it on the line and prevents it from 

 jumping. 



Beginners are inclined to grasp the saw with all 

 the fingers clasped around it. This tends to make 



