It's a Lidgerwood Skidder. There is still one in existance at Camp 6, a logging camp display in Point Defience Park at Tacoma , WA. They were the ultimate in steam yarder/loaders.
HOModeler: Precision Scale in Stevenville, MT had HO models of the Lidgerwood skidders recently. They were all brass, high end models. I think they have just come out with a O scale version.
