These two London barristers vied for success with the ladies:
Huge Johnson, QC, and Engorged Schlong, QC.
Schlong, my own great grandschlong he was, actually wrote the Grove Press book, Memoirs of a Victorian Gentleman, published in the late 1960s when I was at NYU Law studying the Mann Act as applied to consensual, non-monetary sportf**king.

Now you know.

Modernists and historical revisionists may disagree, but this is the true historical origin.

Law Librarian, aka Engorged P. Schlong IV, Esq.
The "P" stands for "pulsating."