Tramp, Tramp, Tramp the Boys Are Marching (1926)
In Tramp, Tramp, Tramp The Boys Are Marching, the words on screen transform into three hoboes (tramps, get it?). On the line And beneath our countrys flag, the word flag transforms into a literal flag emblazoned with a pawnbrokers symbol (another visual joke, as pawnshops are likely to be frequented by tramps).