270 LOGGING 
timber per mile according to the amount of cribbing neces- 
sary. 
Chutes also are used on the Pacific Coast as the terminus 
of a skid or pole road, where the logs are dumped into a stream, 
pond or other body of water. These chutes have a head which 
is cross-skidded like a skid road, the ''slip" or chute proper and 
the "apron" or terminus. The cross-skids at the head offer less 
friction than a pole chute and enable the logs to be readily started. 
The poles in the chute proper are drift-bolted to heavy cross- 
stringers set at 10-foot intervals on the upper part, and 
closer together near the base where the strain is greatest. Side 
poles serve as fenders to keep the logs in the chute. The apron 
extends out over the water, nearly parallel to the surface, in 
order to prevent the logs from striking bottom. The change 
in gradient from the slip to the apron must be gradual or the 
impact of the logs against the latter will soon destroy it. Chutes 
are used only when no other form of transport is feasible for 
even under the most favorable operating conditions many logs 
are broken or damaged. 
In the Northeast chutes similar to the one shown in Fig. 92 
are occasionally built for bringing logs down steep slopes. 
Another form of rough chute used in the same region is built 
as follows: A strip 5 or 6 feet wide is cleared down the slope. 
Logs are then snaked to a skidway at the head of the cleared 
strip ready to be sent down by gravity. The first logs that go 
down are used to form a crude trough of parallel logs down which 
the bulk of the timber passes. Chutes of this character work 
best after a heavy frost or a light snowfall. 
In parts of the Appalachian region the logs are frequently 
brought down the beds of the mountain streams. Where the 
grades are steep and the Ijottom is smooth, little preparation is 
needed, but where the bed is rough, poles are laid lengthwise in 
the stream. The logs are started at the head of a cove and pass 
down the slide with great rapidity, collecting in a rough-and- 
tumble skidway at its base. Although timber is often damaged 
by breakage this is offset by the cheapness of transportation. 
Rail Slides. — Slides for short-distance transportation of logs 
by gravity have been made from steel rails mounted on suit- 
able blocking, where grades are too steep for the use of wheeled 
vehicles. Standard-sized crossties, spaced 10 feet apart, serve as 
