For Craig Smith:  First of all, thanks for helping me identify
a pipe maker.  I rebuilt an old pipe organ several years ago, with
ranks of various pedigrees, and including an 8' free-reed Clarinet.
The pipes were of zinc throughout the compass, the tuning collars
were double-conical (à la Cor anglais) and the reeds were mounted at
a 45-degree angle right above the conical part of the toe.

I was told that the pipes were by Moeller but, as there were no maker's
marks, Aeolian might be a better guess.  The stop does not stay in tune
very well, but it is a really good imitation of an orchestral Clarinet,
especially the characteristic free-reed slow attack.

There is also a discussion of free-reed pipes in Audsley's book,
"The Art of Organ-Building".  As usual, you have to wade through
Audsley's crankiness about "they don't build 'em like they used to."
He shows a drawing of a tuning mechanism that actually tunes the reed
itself, but it looks fearfully complicated.  Anyway, in the Dover
reprint, it starts on Page 611 of Volume II.

For what it's worth...

Jason Neumann-Grable