I have found a picture from of an Oliver No. 36 plow (1913) from the Wisconsin Historical Society which is very close in design to my McCormick Deering plow which I can't identify yet.  Knowing how Oliver was a leader in plow design and the fact that the photo is from the IH archive, I believe that P&amp;O may have been influenced by this one.  If anyone has any information on the exact type of plow this is please let me know.  Thanks!

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