164 
BULLETIN 711, U. S. DEPARTMENT OF AGRICULTURE. 
SWINGING BOOM LOADING DEVICE. 
It has been found in handling medium to small-sized logs in 
heavy stands with the Lidgerwood tree-rigged skidder that not in- 
frequently more logs can be yarded than can be loaded with the guy- 
Fig. 67. — Swinging-boom loading system. 
line loading method. To remedy this defect some operators are using 
a swinging boom of the type shown in figure 67. 
The boom is about 50 feet long and made of a 16 by 16 inch timber, 
tapered down to 12 by 12 inches at each end. The end that is at- 
tached to the head spar tree is stepped on the under side, and has a 
hole about 1 inch larger than the pin. It is fastened to the tree by 
two 2-inch eye bolts. 
