Quelle Wikipedia:

The Webley-Fosbery Automatic Revolver
is a Revolver manufactured between 1901 and 1924
noteworthy for its "automatic" mechanism.
Originally designed by Lieutenant Colonel George Vincent Fosbery in 1895
(using a Colt Single Action Army as a basis), he would later take the design to Webley and Scott, who adapted the concept to their existing top-break designs.
It was built in several slightly different versions, including some with shorter or longer barrels, conventional or Metford rifling, cylinders in .455 Webley or .38 ACP, and even .22 LR
single-shot conversion barrels.
There were only 4,750 Webley-Fosbery Automatic Revolvers built.
The action of the Webley-Fosbery is its most distinctive feature; it's a recoil operated revolver, wherein (upon firing) the upper receiver assembly recoils back to recock the hammer,
and a diamond stud on the upper surface of the frame interfaces with the grooves in the cylinder to cycle to the next cartridge on the return stroke.
This gave it the functionality of a double-action revolver with the consistently light,
short trigger pull of a single-action; while never particularly widespread,
these advantages gave it a niche following among target shooters in the early 1900s.