This is a compensatating double French Horn in F and Bb made by Joseph Lidl  Brun Czechoslavakia. Lidl established his factory for brass instruments in 1895. This horn  features 4 rotary valves, but it is the configuration of the  change valve which makes this design particularly interesting.   The trigger for the 4th valve operates a long rotary valve which re-routes all of the crooks at once. While the wrap of the valve slides on Lidl are different,  I am inclined to believe this is a variation of the Carl Geyer design (which was different from the horn that he produced in Chicago -and also produced by Knopf in Germany where it was known as the Wunderlich model.   The action of the 4th valve is especially fast and the horn plays beautifully.  Scroll down to see a comparison of the Lidl change valve and a normal FH valve.