VOLUME TABLES AND TREE FORM 
167 
Example: Standing 80 feet from a tree, the angle to the top is 
found to be 31 ° and that to the base °, of depression. From the 
tables the tangent of 31° is found to be .6009; multiplying this by 
80 gives 48 feet for the height of the tree above the level of the eye. 
Again the tangent of 8£° is found from the tables to be .1495 and 
this multiplied by 80 gives 12 feet. 48 + 12 = 60 feet, the total 
height of the tree. 
6. Faustmann’s height measure works in much the 
same manner, but gives the desired height directly without 
the use of tables. This instrument may be had of dealers 
at a cost of from $6.50 up. It is compact, not complicated, 
and will be found of great service in estimating. 
SECTION IV 
VOLUME TABLES AND TREE FORM 
A competent woodsman can tell from the looks of a 
tree somewhere near what it will scale, saw out, or yield 
in cord wood according to the practice with which he is 
familiar, and this without any measurements. Or a 
caliper may be used instead of the eye for diameter, and 
some kind of determination made of the height of the 
tree or the length and size of the logs into which it may 
be cut. The point of such judgment and measurements 
as a rule is their wider application. The single tree so 
examined is taken as the type of many, and the stand of 
an acre or of a considerable territory is thus estimated. 
In this process the assumption is made that trees of the 
same dimensions are approximately similar in shape, 
while for the individual tree the fundamental factors de¬ 
termining contents are recognized as height and diameter . 
These two factors in any kind of timber work cannot 
possibly be disregarded. Whatever the scaling or mill 
practice of a locality may be, and into whatever form a 
tree’s trunk is dissected before manufacture, the height of 
the tree and its diameter at some point near the base are 
the chief factors determining contents. These factors, 
consciously or unconsciously, are in the mind of every 
estimator. 
Scientific study of tree form began by making the same 
assumption and selecting the same factors. While it 
