Regarding the posting of John McClelland's MMD 181221 article
("Seek Mason & Hamlin T100 Welte Pianos"), I may be able to shed
a little light on serial numbers associated with T100 Mason and
Hamlin Red Welte upright pianos.

While visiting the Mason & Hamlin factory in Haverhill, Massachusetts,
back in 1990 and 1991, I was extended the courtesy of photocopying
any of the pages from the M&H shipping registers corresponding to the
years from 1920 to 1941.  This time span bracketed the years (1924-1941)
during which Ampico A and Ampico B reproducing piano mechanisms (my
area of interest) were installed in M&H grand pianos.

After reading John's article, I went back to the piano listings
documented in M&H Register Book #7, which covered the serial numbers
from 29,101 to 34,725 (1920 to 1925).  The 'serial number identity'
and detailed characteristics of all pianos (upright, grand, and
player instruments) manufactured and shipped by Mason & Hamlin were
meticulously recorded in their shipping registers.

The objective here was to find any references to M&H upright pianos
that were shipped to Welte in Poughkeepsie, New York, for installation
of the T100 "Red" Welte mechanism.  Because 1920 was late in the game
for "Red" Welte installations, I did not expect to find a significant
number of entries.  However, patience was rewarded with two noteworthy
Welte-related entries.

(Incidentally, does anyone know the street address of the former Welte
factory in Poughkeepsie, New York?  The original building is still
there.)

The first such entry was serial number 29115 (case number 22814) with
a size (style) descriptor of OpMah, with a dull finish, corresponding
to an instrument that was shipped to Welte Mignon, New York on August
24, 1920.  The case number was an in-house working number used to
identify some (all, many) of the parts of each instrument under
construction in the Mason & Hamlin factory.  The second entry was
serial number 29135 (case number 22818) with a size (style) descriptor
of OpMah, with a dull finish, corresponding to an instrument that was
shipped to Welte Mignon, New York, also on August 24, 1920.

With the aforementioned primary source of information as a guide, and
data gleaned from existing M&H Red Welte upright installations, I can
offer a few tentative conclusions regarding what the letters and
numbers identifying the upright M&H Red Welte instruments might mean.
The O notation in the OpMah shipping register designation probably
refers to the model of the M&H upright piano.  A reasonable guess would
be that O stands for 'oversize', because the M&H Red Welte upright is
an unusually large upright piano.

The 'p' notation likely designates the piano as being configured to
house a player mechanism.  The Mah notation almost certainly reflects
the wood finish of the body of the piano, in this case, mahogany.
So far, M&H upright Red Welte piano-identifying numbers (i.e., the
case number) appear in the 22,000 series, but the corresponding serial
numbers per se (as denoted clearly in the M&H shipping registers) have
not been found on extant instruments.

It would seem that the 5-digit numbers that were found on the M&H Red
Welte pianos (sometimes under the keybed or printed on the plate)
have been assumed to be the serial numbers.  However, in all likelihood,
an existing M&H Red Welte instrument's 'identifying number' is the case
number, not the serial number from the M&H shipping register.  What a
surprising circumstance!  How could this happen?

It may be that Welte wanted to 'hide' the origin of the piano in these
particular instruments, to satisfy some mutually beneficial corporate
purchasing agreement between the Welte Corp and Mason & Hamlin.  This
conjecture is a little suspect, because the Mason and Hamlin name
clearly appears (albeit in small letters) molded into the piano plate
in the upper right hand corner.  Whatever the case (no pun intended),
M&H made the pianos in an oversized case, and Welte installed their
reproducing mechanism at their manufacturing facility in Poughkeepsie,
New York.

This author is familiar with one particular M&H Red Welte upright,
with an identifying case number of 22589 (original serial number not
known because my copy of the M&H register does not go back that far in
time).  [In hindsight, I wish that I had photocopied everything that
M&H had that was available to me at the time.] On the plate of that
instrument, it clearly shows the printed notation OpW213.  Based on
sketchy evidence and a bit of conjecture, the W probably stands for
Welte and the 213 recognizes the 213th installation of a Red Welte
mechanism (in an M&H upright, or other upright, or grand, from another
manufacturer?).

Curiously, another M&H Red Welte upright has been found with the
plate identification of OpW966 (piano identifying number is 22,900).
This faintly suggests, but does not prove, that 'many' M&H Red Welte
uprights were originally made.  The current relative scarcity of M&H
Red Welte uprights suggests that the WXXX notations probably also
include the serialized Welte installations of the T100 Red Welte
mechanism in pianos of manufacturers other than Mason and Hamlin,
e.g., Steinway, Krakauer, Welte, Feurich, and perhaps others.

During the course of my M&H re-research, some other notational
oddities in the shipping registers caught my eye.  In 1920, there are
'quite a few' M&H instruments identified with the notation "DMah Pl."
What is a Model D M&H piano, upright or grand (very likely)?  Does the
notation "Pl." reflect the presence of a player mechanism, or does it
just refer to a 'plain' piano case or maybe the type of wood finish
(Philippine mahogany, perhaps)?  If "Pl." does refer to a player
mechanism, what type would that be?  Hopefully, someone in the MMD
audience can address these perplexing, although somewhat peripheral
questions.

Thank you.

Bill Koenigsberg
Concord, Massachusetts