The operator has before him a sheet of green felt, marked off into figured squares-eight to forty-eight. I don’t have to explain the shell game, I guess. We had two shell games, a “cloth” and a “roll-out” team. The most likely, but by no means certain, origin is in a particular con game, as explained in Will Irwin’s 1909 Confessions of a Con Man:

Skidoo is probably a variation on skedaddle, but the twenty-three element is more uncertain. The individual elements, twenty-three and skidoo, are older still.

Twenty-three skidoo makes its appearance in the opening years of the twentieth century, first seeing print in 1906, but being somewhat older in speech. The phrase has engendered a number of mythical explanations, but here is what we actually know. The phrase is actually a combination of two other slang terms, both of them meaning the same as the combined phrase. Twenty-three skidoo, which appears in the opening years of the twentieth century, can be a noun, exclamation, or verb referring to leaving, departure, or making an exit, particularly a rapid one. Like most slang terms, the origin of twenty-three skidoo is not known for certain, but we do have some clues that give us a probable answer. (Updated 14 July 2022 with a reference to the 1899 play of Tale of Two Cities)

Skidoodle skedaddle