Political cartoon showing 1872 Liberal Republicans gathered around a mountain witnessing the birth of its candidate, a mouse labeled "H. G." (Horace Greeley, the candidate for president) with a tail labeled "Gratz Brown" (the vice-presidential candidate).  The scene is apparently based on a quote from Horace (Quintus Horatius Flaccus).
<bdi><a href="https://en.wikipedia.org/wiki/en:Thomas_Nast" class="extiw" title="w:en:Thomas Nast"><span title="American cartoonist (1840–1902)">Thomas Nast</span></a>
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1872-05-18
<i>Harper's Weekly</i>, May 18, 1872, p. 392