Interesting Over-the-Shoulder Cornet from 1850
From the National Music Museum:
“This instrument is one of only two surviving over-the-shoulder cornets featuring three valves and five keys made by E. G. Wright.”
Apparently cornets with both valves and keys were cutting edge at the time because they combined both old and new brass instrument technologies.
Lip-vibrating instruments like the cornet, French horn, and the trumpet are called ‘labrosones.’
I’ve read that over-the-shoulder brass instruments were intended for military performances, the idea being to project the martial music back towards the troops marching behind the band.