226 LOGGING 



track cable also with intermediate supports, an engine with 

 several drums for handling the cables and a series of trolleys 

 which run on the main cable carrying the logs. The trolleys are 

 returned to the head of the tramway on the secondary track 

 cable. 



It is designed to bring logs from a yarding engine to a load- 

 ing device on a railroad at the lower terminus, as shown in 

 Fig. 62. The main railroad extends under the tramway for 

 a sufficient distance to receive the required number of empty 

 cars. The framework supports the engine (25) which drives 

 the drums (3), (4), (5) and (6). The end of the main track 

 cable (7) passes over a sheave (not shown) which has a constant 

 tension on it to prevent undue slack on the cable between inter- 

 mediate supports when logs are traveling between them. The 

 secondary track cable (8) is used for the return of the trolleys 

 to the head of the tramway. The endless traction cable (g) 

 passes over the drum (6) and is shown (10) passing to the upper 

 end of the tramway where it is run through a sheave block and 

 returned, between the intermediate supports, to the drum (6). 



The tramway is operated as follows: With log (11) in the 

 position shown, the operator releases the brake on drum (5) 

 which permits the cable (12) to run out allowing the main cable 

 to lower under its own weight, until it assumes the position 

 shown by the dotted line (13). The log then rests on the car 

 directly underneath it. The tongs (14) are then released from 

 the log and the grips removed from the main cable which is at 

 rest. The hooks (16) are then caught in the carriages (17) and 

 elevated by means of the cable (18) and drum (4) and placed on 

 the secondary cable (8). The grips are then connected with 

 the traction cable (9) which is set in motion by the drum (6) and 

 they are carried to the head of the tramway where they are again 

 transferred to the main cable (7) by a similar device, a winch on 

 the yarding engine being substituted for the drum (4). The 

 main cable is lowered for the attachment of the tongs to the logs 

 in the same manner as the cable is lowered for detaching the logs. 

 When the log has been attached, the main cable is elevated and 

 the grips attached to the traction cable (9). The drum (6) is 



