"The cinéma is an invention without a future," said Louis Lumière.
According to Christopher Rawlence, author of the The Missing Reel, Le Prince made the Accordion Player film of his son playing an accordion the same day and prior to Roundhay Garden Scene. Frames to the film still exist, but apparently haven't been restored like Roundhay and Leeds Bridge. There used to be a website, however, which played the stills in sequence, but it seems to be gone now. One can still see the stills at Wikipedia on the page for Le Prince and other places.