I had the opportunity to puzzle over this beautiful Conn Perfected Wonder Cornet last week.
This model was built between 1906 to 1910, when Conn was still owned by Colonel Conn himself. Some cornet experts believe the patent for this valve design was destroyed by a factory fire in 1911, consequently producing the New Invention Circus Bore model.
A little bit about the mechanism: in C.G Conn's patent application he describes the objective as to, "provide a mechanism which will enable the cornetist at a single movement to instantaneously change the pitch of the instrument and at the same time, and by the same movement, adjust all the valve slides. It cleaned up nicely and the Bb/A conversion mechanism that is fully functional.