"Slide, Kelly, Slide" is a trombone feature tune originating even prior to the '20s. Wilbur Sweatman, considered the first man to cut a jazz solo on clarinet, made an excellent recording of "Slide, Kelly, Slide" in 1919. This and other Sweatman material has been considered well worthy of distribution on retrospective collections in the subsequent decades. The notion that Slide Kelly was also the actual name of a virtuoso trombonist from the early days of jazz is unfortunately a myth, yet not based solely on some kind of enthusiastic misunderstanding of the song's lyrics. The original issue of the song indeed credits one Slide Kelly as the creator of any and all words as well as trombonist George Briegel as the composer of the music.
The former name was just as much a creative act as the "Slide, Kelly, Slide" lyrics, cherished as they are by a certain listening audience that enjoys a combination of novelty silliness and actual technical references involving instrumental technique. The man behind the name Slide Kelly is a familiar one in details regarding publishing frauds, Joe Davis. Davis made use of a series of pseudonyms throughout his long career in publishing, producing, and recording -- at times in order to reroute publishing money owed for songs that were actually in the public domain. Of interest in regard to this history is the fact that Slide Kelly was apparently the very first of these concocted credits.