POWER SKIDDING 249 
logs and returns with the grabs in the rigging sled to the yarding 
machine. 
A dirt road often is used for distances under 2000 feet, but when 
the length of haul exceeds this a fore-and-aft or a pole road is 
constructed.^ Skid roads- were used extensively atone time, but 
they have been abandoned by most operators, although some 
still build skid roads when the conditions are favorable for their 
use. They are more expensive than pole roads since a well 
constructed grade is necessary and from 80,000 to 100,000 board 
feet of construction timber is required per mile, exclusive of bridges. 
The road should l)e as straight as possible because curves 
increase the frictional resistance and reduce the hauling ability 
of the engine and increase the wear on the cable. Rollers are 
placed on stumps or posts, or fenders are put alongside the road 
at curves to reduce the wear on the main cable. 
During the early period of logging in the Northwest the road 
engine sometimes was replaced by a geared locomotive and the 
logs were dragged between the rails from the yarding engine to 
the landing. As a rule, the logs were dragged over the cross- 
ties, but on a road of some permanency planks were spiked on 
the ties to protect them. A plan sometimes followed was to 
have a spur track from ^ to 1 mile long running out from each 
end of the landing, with a donkey working at some point on each 
spur. The engine went out one spur and with a short cable it 
coupled to a turn of logs, made up in advance, and dragged them 
to the landing. It then went out the other spur and brought 
in a turn from it, alternating in this manner throughout the day. 
A water tank with a 1^-inch escape pipe was used to wet the 
track to facilitate the passage of the logs. On a 1-mile haul 
one engine handled daily the output from two yarding 
engines. 
FUEL REQUIREMENTS 
Wood is the fuel most commonly used in power skidders in 
all parts of the country, although coal and fuel oil are used in 
regions where they are readily available. 
From the steam-producing standpoint wood is a fairly satis- 
factory fuel for average logging conditions since it can be secured 
on the operation and is seemingly cheap. When heavy demands 
1 See page 268. " See page 148. 
