Autograph Record Year

Hi all,

While looking through a box of records in an old game shop in Minneapolis today, I stumbled across an awesome Autograph 78 rpm record that was made by Marsh Laboratories (you know, the kind with the red checkered label border and the word "Autograph" in fancy script). I had to shell out a lot of money - a whole dollar - to allow the store owner to let me have it, but it's definitely worth it. The music on both sides are two virtuoso concert pieces by Chopin and Schumann ("Dwaj Grenadierzy"/"Hulanka") sung by an amazing-yet-completely-forgotten basso named Franciszek J. Rosenthal. The piano accompaniment is by a woman named Katherine Hoffman. My guess is that this is a vanity recording but I could be wrong.

This record has no record number, but it does have the matrix numbers "4026" and "4027" stamped in the dead wax. My question is when was this record made? I know Autograph shut down in late 1926 but since they started making electrically-recorded discs in 1924, are there any clues I can use to figure out a date when the record was made? Also, does anyone have any information about Mr. Rosenthal or his accompanist? The sheer power and skill of his voice makes me believe that he had some serious, high-level musical training but searching has revealed no information about him whatsoever.

Thanks!