In 1911, army appointed a board to select a general purpose soldier's
shoe. After exhaustive study and testing, they selected a last designed
by Surgeon-Major Munson, the famous "Munson last." A characteristic was
the straight inner-side, aligning the big toe straight ahead, and the roomy toe area, to allow free movement of the toes. No compression on arch or instep. No hooks to catch in grass or bend out of shape. Single sole to allow flexibility. Intended for marching/walking, the thin leather was not intended for wet conditions; was not waterproofed.
Lower, wider and longer than normal heels.
This is the famous brogan, "clod-hopper," "Li'l Abner" shoe still around in the early 1950s, at least, and prompted the WW II draftee joke about shoes being so big he could execute an "about face" and the shoes didn't remained in place.
Sorry not to have detailed specs, but perhaps the 1911 date can serve as point of departure unless others have more information. Mine from Horace Kephart ("Camping and Woodcraft," 1906, reprinted in 1917 and 1921 editions by Macmillian, NY. I am drawing from pp. 151-153 of 1952 16th printing of two-in-one 1921 "New Edition." For rugged terrain and wet, Kephart recommended waterproofing formula and placement of hobnails.
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