Unusual use for a single-driver "bicycle" locomotive, that would seem to have barely enough traction to move itself, let alone a train of heavy logs.

http://cgi.ebay.com/6226ND-RAILROAD-PHO ... otohosting

That little loco is a Mason "pony". In 1861 & 1862 Mason built a half dozen or so of these little 2-2-0's for lines in the northeast and midwest. They had 9x20 cylinders, 54" drivers, and weighed 12 tons. TE was 5600 lbs. At least one was rebuilt to a 4-2-0. There are a couple of additional photos in Arthur Wallace's book "Mason Steam Locomotives"