166 A MANUAL FOR NORTHERN WOODSMEN 
by the face and adjust the hold till the end of the staff 
just comes by the eye. The distance from the eye to the 
staff and from the hand up to the end of the staff are now 
equal. Go off from the tree to be measured, holding the 
staff erect, until you can sight by the fist to the base of the 
tree and by the top of the staff to the top of the tree. Pace 
or measure to the tree and this will give its height. 
4. The Abney clinometer, shown on page 93 of this 
work, may be used for height measurement in much the 
same manner. Set the level tube at an angle of 45° with 
the line of sight and go off from the tree on a level with 
Faustmann’s Height Measure 
its base until, sighting at the top of the tree, you see by 
the bubble that the tube is level. The distance from the 
observer to the tree is then equal to the tree’s height. 
5. A second method employing the same instrument 
is as follows: Stand at a point where both the top and the 
base of the tree can be seen and at some convenient dis¬ 
tance from it, as 100 feet. Sight to the top of the tree and 
observe the angle of inclination, and again to the base of 
the tree, observing that atigle also. Go into the table of 
tangents with the angles in turn, find the decimals corre¬ 
sponding, and multiply by the length of base. The sum 
of the two figures is the total height of the tree. 
