>>117179631It's a reference to a painting called "Phryne before the Areopagus," where a courtesan (Phryne) was placed on trial in Athens on charges of impiety. Since the trial was going against her, her lawyer, the orator Hypereides ripped off her robes before the jury, who acquitted her and dropped the charges (because they were simps and coomers).
In the Puck cartoon, the role of Phryne is being taken by the politician James G. Blaine, who had a lot of scandals associated with him (tattooed on his body), but had still managed to secure the nomination as the Republican contender for the 1884 presidential election, decided in Chicago.