What do the hallmarks mean on old single shot webley and Scott pistol?

Firearms, when manufactured, as subject to a "proof" firing with a powder charge larger than standard. In European nations, they would be "proofed" at the government proofhouse. To show that a firearm had been tested, "Proofmarks" would be stamped on the firearm- and for a revolver, the frame and cylinder were both marked. Proofmarks would show roughly what era it was made, and which proof house tested it.