This strange instrument is a mellophone, tuned in C (/B). No signs on maker.
The appearence is close to some few prototype instruments, Antoniophones, made by Antonio Courtois
in the late 1800's.
Tis instrument can turn the bell, so that it points forward, useful when marching.
It is playable, but not very handy to work with. Probably made between 1910 - 1930.