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LOGGING 
Guy-line System. — This is a common method of loading logs 
which have been yarded by an overhead or high-lead system.^ 
A standing line, usually a guy line for the spar tree, is stretched 
across the track and from this is suspended a block at a height 
of about 60 feet above and directly over the center of the track. 
Loading Block 
Loading Block 
From Bulletin 711, U. S. Dept. of Agriculture. 
Fig. 128. — A Single Guy-line Loading System. Pacific Coast Forests. 
The loading line passes from a drum on the yarding engine or 
loader up to and through a block on the head spar and thence to 
and through the loading block. This method is not capable of 
handling a very large yarding output. When this is necessary 
two loading lines may be used. 
Swinging-boom loaders. — When logging with an overhead sys- 
tem in small- to medium-sized timber, loading equipment of the 
type shown in Fig. 129 may be used. An end-control swinging 
boom about 50 feet long is supported at its base on the head spar 
tree, and at its outer end by a cable which is also attached to the 
upper part of the spar. The boom may be moved in a radius 
of 90 or more degrees by means of the swinging lines, each of 
» See Fig. 128. 
