256 LOGGING 
trees. The cable rested, free, in a slot in a casting bolted to 
the end of the brackets, except in depressions where one end of 
a piece of strap iron was riveted to the outer side of the casting 
and the other end passed over the cable and was nailed to the 
bracket. 
A log was carried by a pair of trolleys, each having two sheave 
pulleys which ran on the upper side of the cable. Two short 
chains each having a ring on one end and a "grab" on the other 
were used for attaching the logs to the trolleys. 
Five sets of trolleys were joined together by a f-inch cable, 
which was wound around a drum, equipped with a friction brake, 
which was placed at the head of the tramway and served both 
to control the speed of the descending load and to return the 
empty trolleys to the head of the tramway. Power for the 
latter purpose was supplied by a 6-horse-power gasoline engine. 
The logs were loaded on the tramway from a set of balanced 
skids which were placed so that the short ends of the skids were 
directly under the main cable. Horses brought the logs to the 
base of the balanced skids upon which they were rolled. The 
grabs were then driven and the skids elevated until the rings 
on the grabs could be fastened in the hook on the trolleys. 
The maximum capacity of the tramway was 6000 board feet 
per turn, and approximately thirty minutes were consumed in 
making one round-trip. 
A similar tramway has been used in the Northwest for elevating 
logs from canyons to plateaus. The cable was suspended between 
two points and the loaded trolleys were hauled to the top by a 
hoisting engine. 
A special adaptation of a single-wire tramway^ has been used 
on an operation in the Northwest for lowering logs on grades 
up to 60 degrees. The main cable was IJ inches in diameter 
and 1500 feet long. It was attached at the head of the tramway 
to a large tree at a height of 75 feet. The tree was braced se- 
curely on three sides with guy wires. A 16-inch sheave block 
was spliced to the lower end of the main cable and through this 
block a 1-inch cable 150 feet long was passed. One end of the 
latter was attached to a stump and the other to the drum of a 
yarding engine, both stump and yarding engine being in front of 
and equidistant from the sheave block. The main cable could 
1 See The Timberman, Aug. 1909, p. 24. 
