When In doubt, Google is your friend:
"This Vancouver City Archives photo of just-trimmed skids for a donkey engine is one of the best I’ve seen for sharpness of detail.
"Taken in the 1920s, it’s quality should come as no surprise because it’s a Leonard J. Frank (1870-1944) shot. He’s without doubt one of British Columbia’s finest industrial photographers whose work is in many museum and archives.
"The logs were felled on the British Properties, by the way. You can judge their original diameter by the man posing with the broad axe."\
Here is a much smaller one, but you can see the design.

Spotlight on Dolbeer Spool Donkey
The Dolbeer spool donkey was was built in 1894 and owned by Chemainus Lumber Co. It was purchased from National Iron Works in San Francisco...
Cool picture Sonic... I learned something today!
Sirhr