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Horse logging with 8 wheel trailers like this one could help you to get over uneven ground and different obstacles in your skid path without turning everything over.
Notice how the axles move and float independently of each other and never leave the ground.
This could be used with a single or more than one horses/mules/oxen.
Notice that half way in the video a logger is loading logs by hand using a small hand held set of tongs to load with by himself.
http://www.youtube.com/watch?v=GVq0j5gv_dw
bumpus
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