"Under dog" at Yale, 1871 (a "dog day" etymology)

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    BDE has 1887 for "underdog."
    The Making of America database shows this from the 1870s.
    Lyman Hotchkiss Bagg's FOUR YEARS AT YALE (1871) has "the under dog in
the fight" on page 81.
    "The under-dog in the fight" is also in OVERLAND MONTHLY AND OUT WEST
MAGAZINE, June 1872, pg. 520.
     "...the public...valiantly sides with the under dog, otherwise the
artist" is in APPLETONS' MAGAZINE, 8 August 1879, pg. 189, col. 2.
     A "dog day" etymology.