32 BULLETIN 440, U. S. DEPARTMENT OF AGRICULTURE. 
The greater portion of the wood used consists of limbs, especially 
sugar pine, cut into lengths on the ground. This limb wood may be 
carried to the yarder by the woodbuck or packed on a mule for small 
machines. For larger machines, it may be dragged on a sled by 
either one or two horses, or hauled in a two-horse cart. In a few 
instances in the northern Sierras sound Douglas fir logs are cut by 
hand into fuel at the yarder. Some companies use slab wood cut at 
the mill and hauled to the woods on logging flats. Still others cut 
wood from white fir, allow it to season, and then deliver it to the 
yarders on flat cars. 
The cost of supplying fuel at one of the smaller compound engines 
is the time of one man and a horse, or about $3.50 per day. At the 
10 by 11 inch and 10 by 13 inch machines, on the East Slope, burning 
slab wood, the cost is about $4.25 per day for the time of one man 
and the handling of from 1§ to 2 cords at each machine. Where the 
split fir wood is used, the amount required daily for a 10 by 10| 
machine is 2 cords, costing $2 each. The large 11 by 13 inch yarders 
require about two men and a horse to furnish limb wood, at a cost 
of $5.50 per day. Similarly the 12 by 14 inch machines on long 
settings require two men and a light team at a cost of $6.50 per day. 
The first method of supplying water to donkey engine boilers 
was by packing in water bags on mules. One waterbuck and mule 
is required for small boilers, at a daily cost of $3.25. Large boilers 
require double the force. At present this method is relegated to 
donkeys used on railroad and chute construction, and donkey engines 
are supplied almost universally by water conveyed in pipes. Where 
water is abundant, about one-half of the machines can be supplied 
by gravity. Where water is less plentiful, from three-fourths to all 
of the machines must be supplied by pumping. The cost depends 
upon the distance water must be piped and the number of machines 
that can be supplied from one pump. Usually two or three machines 
can be reached from a pump, and the daily cost for hire of pump- 
man, repairs to pump, and the prorated cost of stringing pipe, is 
from $1.50 to $2 per machine. The depreciation on pipe and pump 
varies from 44 cents to 75 cents per day. In localities where water 
is scarce the best method of supplying water is by means of tank 
cars. The daily cost, including hauling and depreciation, is from $3 
to $3.50 per machine. 
Maintenance. — A very considerable cost in yarding is the main- 
tenance of the cables. The fife of a main line varies from one- 
half to l\ seasons, depending upon the usage, the amount logged, 
the amount of rocks, and the general difficulty of logging. 
Under the favorable conditions in the yellow pine in the eastern 
Sierras, a lj-inch main fine will last from one to two months more 
than a season and a back fine two or t?hree seasons. The average 
