A 1908 New York street musician

A 1908 New York street musician, playing the cello and the violin at the same time:

One could speculate about what he was playing. Perhaps e.g. Beethoven's Rondeau Concertant No.2, Op.51
 for violin and cello ? Probably not, as the cello part would have been rather difficult to play with the technique
used by the musician in the picture.