Credited in The Reader’s Digest, August 1936 · identity uncertain
Channing Pollock is the name printed beside the earliest known appearance of this joke — a reader submission to The Reader’s Digest in August 1936. Quote Investigator is careful here, and so are we: a Channing Pollock (1880–1946) was an American playwright and drama critic; a second Channing Pollock, the movie-star magician, was only ten in 1936 and is ruled out on age. QI still declines to confirm the playwright is the submitter — “it is not certain that the joke submitter Channing Pollock is the same individual.” Pollock’s own phrasing suggests he was not the author either: he opens with “Do you remember the sailor who…”, which is how you retell a joke, not how you coin one.