38 FOREST UTILIZATION 



Double block carriage with different ial hoist 



and log grip ; 



Brackets, supporting the cable ; 

 Steam engine with hoisting drum ; 

 Lateral hauling-in rig, by which logs are 

 dragged to the main carrying line over 



distances running up to 1,000 feet, 

 (b) In case of electric power, the outfit, 



costing $6,200 per mile, consists of : 

 One-inch carrying cable and ^2-inch single 



current rope, which is swung thrice 



over a grooved sheave ; 

 Generating machines and 2O-horsepo\ver steam 



engine ; 

 Carriage, including the log support and the 



motor with sheave, which has a speed 



of six miles an hour. 



I. Loading arrangements are required, wherever vehicles are used, 

 except for bummers. 

 I. Loading on wagons. 



(a) Sliding logs from a higher bank onto vehicle* 



Only one layer can thus be loaded conveniently. 



(b) Rolling logs up an incline, either with peavi 



or rope, the top of the incline resting on the 

 tops of the wheels. 



(c) A (drum) winch in front of wagon, incline be- 



hind wagon, pulling logs up by rope. 



(d) Tackle block attached to a tree, the wagon stand- 



ing between the tree and log; the end of rope 

 attached to outside wheel and the free end 

 pulled by animals. 



(e) The skidway scheme. Trained horses running 



on prepared track opposite the skidway. Two 

 poles leading from skidway to wagon ; rope 

 running from outer wheel of wagon under and 

 around the log and back over the wagon to the 

 horses. 



(f) A jack, consisting of a gear wheel and a toothed 



iron rod. 



(g) German lever arrangement. 

 II. Loading on railroad cars. 



Additional methods. 



(a) A huge tripod and Weston's differential hoist. 



(b) A drum and wire cable rig, the loading cable 



running over a tackle block suspended over 

 track. 



(c) Cranes or derricks as used on the harbor docks, 



a special make of which is known as the 



