A 
PREFACE 
The reception accorded this book since it was first 
issued in 1909, particularly the appreciation expressed 
by numerous woodsmen, has been gratifying. Letters 
of commendation have been received from users in 
all parts of the country. It is significant that the 
first typographical error discovered (a wrong figure 
in a logarithmic table) was pointed out by a ranger 
on the largest tract of unsurveyed timber land in the 
United States, in Idaho. The second correction was 
sent in by a Canadian cruiser. 
The incidents just mentioned illustrate the wide 
distribution of the volume and explain the present 
extension of it. As originally written, the book did 
not aim at circulation west of the Lake states; but 
from the first a large part of the demand for it came 
from Westerners, chiefly those employed in the 
United States Forest Service. Revisions have been 
guided largely by this fact, and that is true especially 
of the present and first considerable revision, for 
aside from bringing the work up to date as concerns 
appliances and methods which have come into use 
since the first edition was written, the new matter 
and tables which have been introduced are mainly 
intended for the benefit of western woodsmen. As a 
result, material additions have been made under the 
heads Topographic Maps and Timber Estimating. 
