PRACTICAL FORESTRY. 



tion, a,nd considerable judgment in taking the average will, 

 however, be required. 



When each tree is to be measured separately two assistants 

 will be required, one to carry the 18-ft. .pole, and the other 

 the girting-strap. Sometimes, when the timber is of great 

 height, jointed bamboos are used, and a light ladder brought 

 into request. 



In going to work, the man with the pole declares the height 

 of the tree, and the one with the tape the quarter-girth. 



Measuring the height of trees- There are several 

 methods of ascertaining the heights of trees, but the two 

 following are, perhaps, the most simple and the appliances 

 inexpensive : 



No. 1. Take three laths, such as bricklayers use for 

 tiling, and nail them in the shape of the frame ; a a must 

 be of equal length ; a and b being placed on the ground, the 

 eye must follow up the larger lath d d until it is in a line 

 with e, the top of the tree or object you wish to measure. 



The frame must be placed as level with the bottom of the 

 tree as possible. Should the ground be very uneven you 

 must give and take accordingly. 



It will be seen that b to c is the same length as b to e, 



No. 2. Suspend the triangle between the thumb and 

 forefinger of the left hand, knuckles down, upon the point 

 a a, allowing it to swing freely. The edge b c will then fall 

 perpendicularly, and c d will be horizontal. The remaining 

 edge d b will then lie at the angle of 45 to the horizon. On 

 this edge are two sights, e and/. Look through e until /ie 

 aligned with the tree-top, advancing or retiring till the sights 

 point exactly to it. 



Then, if the observer's feet aie level with the tree root, the 

 height of the tree is the distance from his feet to the root, 

 plies the height of the eye from the ground. 



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