In yesterday's Digest Angelo Rulli asked for info about above firm.
In the book, "Piano and their Makers", by Alfred Dolge, at least some
information is given.  In the Appendix a list of firms, active at the
time of publishing of the book (1911), contains:

   Kurtzmann, C., & Co. Est. 1848, however not in Boston,
Massachusetts, but in Buffalo, New York.

In the Index we find a Kurzmann, Christian, to be found on page 292.
This is a page in the chapter "Men who have made piano history".  A
picture of Mr. Kurtzmann is on this page, and the text says:

  "Following the chronological order, we find that Christian Kurzmann
   established a piano factory in Buffalo in 1848.  After his death in
   1886, the business was taken over by a corporation".

Maybe these new owners moved the company to Boston?

Jan Kijlstra