Since the Days of Leij Ericson 



691 



for carrying the front end of the load. 

 Other devices, such as the skidding 

 pan, the tractor-drawn scoot, and 

 the tractor-drawn wagon on crawler 

 treads, have been highly successful. 

 They have nearly supplanted cable 

 logging except in the heaviest timber 

 and on the steep and swampy lands. 



LOADING has also gone through sev- 

 eral stages of development. First it was 

 found that logs could be rolled up in- 

 clined skids easier than they could be 

 lifted. The skidway or brow built out 

 from a hillside to hold logs off the 

 ground at about the height of the haul- 

 ing vehicle was the next step in the 

 development of loading methods. But 

 as the logs and the volume to be 

 handled got bigger, hand loading rap- 

 idly became obsolete. Power loading 

 came into use. First came the cross 

 haul, by which horses or a tractor can 

 be used to roll logs up inclined skids 

 onto the hauling vehicle. Next came 

 the jammer, an inclined A-frame with 

 a sheave at the apex over which the 

 loading cable could be passed to give 

 a lifting as well as a pulling action. 



Then came a variety of jib booms and 

 cranes, some mounted on stationary 

 spars, some on sleds, some on crawler 

 tracks, and some on pneumatic tires. 

 These made the loading job much 

 faster and easier. In recent years a 

 number of types of self-loading trucks, 

 with cross hauls, jib booms, or flippers 

 powered from the truck motor have 

 been put into use on smaller jobs. 



The last part of the logging job to be 

 mechanized has been felling and buck- 

 ing. Chain saws, consisting of teeth 

 mounted on a bicyclelike chain, were 

 introduced from Germany about 1924. 

 The cutting chain runs around a 

 grooved steel guide bar and is powered 

 by a small gasoline, electric, or pneu- 

 matic motor. Recent improvements 

 have made this a reasonably reliable 

 tool. It is now widely used through- 

 out the country. 



In the flat, open pinelands of the 

 South, a circular saw mounted ahead 

 of a wheeled frame like that of a gar- 

 den cultivator has proved useful. The 

 power is provided by a small gasoline 

 motor mounted between the shafts of 

 the frame. The saw can be used either 



Home-made calipers for measuring the diameters of trees. Hold breast high (4Y 2 feet 

 above ground) and read diameter of tree direct from the caliper. 



