Hi there. Am trying to find out, where an air-powered car horn may have been in service. The horn is bell-shaped, made from black-painted brass. Bell-shaped part is ~ 5½ " (143 mm)long, ~8½" (214 mm) including "mouth piece". Inner, suporting section is iron. On the outside, there is a coin-like badge saying Powell & Hammer Ltd., Birmingham.
Somehow, I suspect it might be from a british car ;-)
Any help would be very much appreciated,
Your's Lars Denmark