There were two separate steam engines, one each side of the boiler, each driving one track on one side through its own spur gear reduction and driveshaft. A differential was therefore not required.
Note the need for a steersman at the front. This was a highly vulnerable position for the log sleds had no braking system (and neither had the logger!) so if the sleds began to overtake the logger on a downhill slope, it would be likely to jack-knife the logger and swing it off the track into the nearest tree; the steersman had to be very good at jumping clear.
Since logging required icy condition the steersman was also exposed to sub-freezing temperatures going down to 40deg below zero. Many loggers had small cabins at the front to protect the steersman, but this limited his ability to jump for his life when necessary. If no cabin was fitted an additional hazard the steersman faced was the danger of having his clothes set on fire by cinders from the chimney.
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