Thanks to all who furnished information regarding the Erbar Initials.
The only primary source materials I found was a printing of the
Initials by a San Francisco printer, dated 1924, and the information
below* as provided by RIT.
Based on secondary sources it would seem that Jakob Erbar (the
designer of the Erbar sans, a source of confusion) was the designer
for the Initials. Oddly though, the Initials seem never included in
listings of his designs. And, unless I missed an email or two, none
of the sources indicated a date of design for the Initials.
Secondary sources also indicate Ludwig & Mayer as the foundry of
origin (Erbar designed for this foundry). The importer, Continental,
later Amsterdam Continental, did handle distribution for Ludwig &
Mayer. The Cary Graphic Arts Press indicated that the face does show
in Continental's specimen books of around 1929.*
Apparently Melbert Cary of the Press of the Woolly Whale was fond of
using the initials in combination with Eve. The RIT Cary Collection
has a current showing of the Press of the Woolly Whale.
Ludwig & Mayer also sold matrices to the US market for some of its
faces. Not uncommon. Castcrafters of Chicago cast a number of Stemple
faces, such as Optima and Palatino, from Stemple matrices. The
casting I have however indicates it was ground to .918 for the US
Amsterdam was suggested by a couple of correspondents. I did check
through the Amsterdam catalogs that I have and it is not there,
though they did cast the Erasmus Initials, which are often confused
with the Erbar. The Initials I have likewise do not have the common
t/a pinmark. Similar to other Ludwig & Mayer castings I have, there
is no pinmark.
So, that's the story thus far. Again, thanks one and all.