108 THE WOODSMAN'S HANDBOOK. 



structed so that when pressure is applied to its inner edge, as when 

 it is brought against a tree trunk, it swings into a position in which 

 it is at a true right angle to the beam. 



For use in eastern forests the most convenient caliper is one 

 having a beam measuring 36 inches and arms half that length. 

 Cost, $4. In forests where trees over 3 feet in diameter occur 

 a caliper having a beam measuring 50 inches and proportionately 

 long arms should be used. 



FIG. 13. Cruiser's tree counter. 



Care should be taken to secure calipers made of perfectly sea- 

 soned wood, for otherwise they will warp. Calipers graduated to 

 show the contents of logs in board feet or cords are being intro- 

 duced in many sections of the country. 



DIAMETER TAPE. 



This is a tape for ascertaining the diameter of very large trees, 

 such as the redwoods of the Pacific coast. It is furnished with 

 special graduations, so that when the girth of a tree has been 

 measured its diameter is read directly from the tape. No cut of 

 this tape is shown. 



