Regarding the Mowry's Songster, which is said to be the source of Charlie Poole's version:

A copy of Mowry's Songster is listed in the Guthrie T. Meade Collection #20246, Southern Folklife Collection, The Wilson Library, University of North Carolina at Chapel Hill. (Folder 679:        
Mowry's Songster). If anyone is in the Chapel Hill/Triangle area, perhaps they can investigate it.

--Charlie Baum, who heard Larry Hanks and Deborah Robins sing the Baltimore Fire song last night, and sparked my interest in the subject