312 LOGGING 



due to gravity, rolling friction, and curve resistance, and trien 

 deducting from this result the weight of the locomotive and ten- 

 der. This gives the tonnage the locomotive can haul, including 

 the weight of the cars. 



The estimated hauling capacity of locomotives of given weights 

 and types can usually be found in the catalogues of the manu- 

 facturers. 



The following figures were secured from logging operations. 

 On a 24-degree curve and on a 3.5 per cent grade, two 40-ton 

 Shay engines have hauled six loaded fiat cars^ containing 42,000 

 feet board measure, while the same locomotives have hauled 

 eleven cars, 77,000 feet, over 32-degree curves and a 3 per cent 

 grade. A 60-ton Shay on the same operation hauled five cars, 

 35,000 board feet, over a road having 24-degree curves and 3.5 

 per cent grades; and eight or nine cars, of 7000 feet capacity 

 each, over a 32-degree curve and a 3 per cent grade. A 18-ton 

 Shay, operated on a road four miles long and having grades 

 ranging from o to 8 per cent, and with one 47-degree curve 

 handled daily 150,000 board feet.- A 50- ton saddle-tank, rod 

 locomotive operated on a road having maximum grades of 2 per 

 cent and curves of 30 degrees has handled eight loaded skeleton 

 cars with safety, 



FUEL FOR LOCOMOTIVES. 



The fuel used on logging locomotives may be wood, coal, or 

 crude petroleum. 



Wood is frequently used in regions where coal and oil are 

 expensive; because of heavy transportation charges, however, 

 it has several disadvantages. 



(i) There is danger from forest fires during the dry season 

 because sparks are thrown for long distances. A great percent- 

 age of the forest fires on logging operations start along the 

 railroad. 



(2) There is a large bulk of material to be handled. It 

 requires twice the amount of wood as compared to average 



^ Length 41 feet; weight of each car ^7,000 pounds. 

 2 The Timberman, September, 1910. 



