There is probably no overall "numbering scheme" to give a grand unified
picture of Aeolian piano-roll output over its 40 years of production.
It's clear, however, that some effort went into allotting numbers into
discrete blocks to keep the various 65-note (65n) and 88-note (88n)
issues separate in both London and Meriden, Connecticut, production.

The two roll factories used somewhat different ways of presenting the
same material in terms of prefixes and cost-codes, which makes the
patterns harder to see. The rolls for other instruments were quite
separately numbered, notably the Duo-Art not fitting into an 88-note
scheme. They of course didn't need to.

There were two quite distinct Aeolian products: the brands for sale by
Aeolian dealers (Themodist-Metrostyle, etc.) and identical rolls with
a generic brand for anybody to sell, catalogued as "Universal" but with
anonymous labels so shops or resellers could use their own brands.

All this, of course, started in the 65-note era, and 88-note rolls were
fitted into the numbering scheme later. We see history from now looking
backwards so later rolls rather mask the earlier ones, but analysis of
production must start with the oldest (and to modern ears the least-
interesting) output.
 
It is a mistake to call the generic issues by their roll format: the
brand was "Universal", as per the roll catalogues. To help buyers
identify suitable rolls for their instruments the labels described
their format. At the start 65n didn't need qualifying because it was
the only piano-roll format, but 88n when new required special labelling
and labels described it as "88 note", "eight eight" or "full scale".
But these were and are technical descriptions, not brands (like disc
records where "78" is not a brand even though most discs say it). Later
65n production did say its format on the label once possibilities for
confusion had arisen.

As new ideas appeared, notably the Metrostyle and later Themodist
in the 65n era, new series appeared to market these higher-priced
rolls. When the 88n format _was_ introduced it was only sold branded
as Metrostyle and/or Themodist according to what was on the roll.
The generic Universal product was a plain 88-note with neither 'extra',
although later the Universals got theme accenting, presumably because
it was cheaper to perforate only one format and just mark the paper
differently.

Aeolian were quite careful to number all of this complex output in
one scheme, using (mostly) 5-digit numbers where the first two digits
indicate the roll format. London used the Meriden numbers when using
imported masters but supplemented this with series of their own, with
an L prefix.

Duo-Art roll numbers are a bit of a mess because price codes were
appended to the issues in Meriden but never in London. If codes are
ignored, classical Duo-Arts start at 5500 in 1913 and ran up to about
7600. There were a variety of dance rolls with an abrupt change of
numbering in the mid-1920s. And a number of separate series for
different musical genres, mostly with relatively few titles. These
are all well covered by the Charles Davis Smith "Complete Catalog of
Duo-Art Piano Rolls".

Many years ago I wrote up the Aeolian 65n & 88n number blocks for the
Player Piano Group Bulletin, issue 140, Autumn 1996. I'll post it here
separately.

Julian Dyer
Wokingham, Berkshire, UK