There used to exist a "Spanish Trumpeteer" that was invented and built
by Fredrich and Theodore Kaufmann, maybe between 1837 and 1851. The
business was begun by Theodore's grandfather Johann in 1752. The
remains to this day are still in the Deuches Museum in Munich, Germany.
I still have a postcard from the museum with a color picture of it. It
was a valveless trumpet, the notes being produced only by the mouth,
and the machine was so accurate that it could blow double notes of
equal strength and purity. Besides blowing octaves, it could also blow
4ths, 5ths, and 6ths. The lips were covered with leather. There's a
little story about it in the Encyclopedia of Automatic Musical
Instruments, pg. 480.
What we are privileged to see and hear today in pneumatic instruments
is but a fraction of the accomplishments set forth by our forebearers,
long before there was such a thing as a "patent" office.