110 



THE woodsman's HANDBOOK 



THE PRESSLER INCREMENT BORER. 



For extracting a solid plug of wood from a standing tree in order 

 to count the rings in the la.st 1 or 2 inches, with less injury to the 

 tree than cutting a notch for this purpose. 



Fig. 15.— Pressler increment borer. 



The instrument consists of three essential pai't^: ^ 



A hollow steel auger (A) 3 or 4 inches long, tapering and threaded 

 on one end and a square 



shank at the other to fit in /K^^S^ESiiS^^^^^^ 

 the square eye of the hol- 

 low handle (B). (C) is a 

 pin -shaped wedge with 

 toothed end. The auger 

 and wedge are carried in the hollow handle (which is fitted with 

 screw caps) when not in use. 



In using the instrument it is bored into the tree toward the 

 center. As the thread forces the auger in, the knife edge sur- 

 rounding the oi)ening of the auger cuts a solid cylinder of wood f ) 



Fig. 10.— Core extracted, showing rings. 



