TromboneChat

Seen in a 19th Century back cover blurb for publications available...

Try this explanation: an Adolphe Sax "valve arrangement" trombone: Trombone Saxomnitonique

https://music.allpurposeguru.com/2011/0 ... olphe-sax/

In 1818 Dupont applied for a license for an improved model, signed by J.C. Labbaye. Finally, the “saxomnitonique” built in 1824 by A. Sax from Dinant, had the most success.
The “cor omnitonique” had very many turns and was therefore quite heavy.
http://users.skynet.be/french-horn/gesc ... denis.html

Hope this helps...

...Actually, it doesn’t play perfectly in tune, but nothing in the education of trombonists provided sufficient attention to ensemble playing that anyone realized that yet.

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