LOGGING IN THE DOUGLAS FIR REGION. 113 
Eepair parts, materials, etc., other than labor, and iron and steel 
bars, for three 10J by 10J inch, compound-geared engines for six 
months cost $216, or $72 per engine. This is at the rate of $150 per 
engine per year. The engines were about 3 years old, working in 
better than average ground, and receiving good care. The repair 
parts, materials, etc., for six yarding engines for one year amounted 
to $1,200, which is at the rate of $200 per engine per year. The 
engines were about 5 years old and worked hard. 
The total cost of taking out old flues and putting new ones in a 
yarding engine amounts to about $420, as follows : 
Cost of 282 flues $282. 00 
Cost of freight 6. 00 
Cost of 5 men for 7 days 134.00 
422.00 
The cost of putting in a main-drum shaft amounts to about $244, 
as follows : 
Cost of labor___ $106. 00 
Cost: of new shaft— 131.00 
Cost of freight 7.00 
244. 00 
Appraisers of National Forest timber estimate the annual cost of 
the upkeep of yarding engines at from 8 to 10 per cent of their orig- 
inal cost, the amount being equally divided between labor and ma- 
terial. 
Depreciation on yarding engines. — No class of equipment is called 
upon for such extremely severe service as ground yarding engines. 
The demands made upon them are frequently far beyond their normal 
capacity. In addition, it is difficult to give them the attention they 
should have to keep them in good running order. This results in a 
relatively short life. 
It is not possible to more than approximate the life of the ground 
yarding engines which are now being manufactured. There are 
several reasons why this is true : 
(1) Ground yarding engines have undergone many changes, and 
those on the market are stronger than those built even a few years ago. 
The only basis for estimating the life of the present-day engine is 
the length of service secured from engines that have been or should 
have been discarded, taking into consideration the period of efficient 
service and the question of obsolesence. There are yarding engines 
working in camps that are 12 or 14 years of age. It may be, however, 
that it would be profitable to replace them with new engines ; that the 
increased cost of logging, because of obsolesence and high maintenance 
costs, more than offsets the effect of a lower depreciation charge and 
a lower fixed investment. 
61361°— Bull. 711—18 8 
