In April, May, and June of 1916, Joplin made seven hand-played piano rolls, six for the Connorized Company and one for Uni-Record.
The last one - "Pleasant Moments" - was unknown until a couple of years ago, then found via an ebay purchase (the rolls had been in the wrong box).
The recovered roll file was perforated in London and recorded by pianolist Worn Axles on a Steck grand piano.
This version of Maple Leaf Rag
is from the roll for Uni-Record, 1916 (published originally 1899).