This unusual British cartridge revolver is marked on the top strap London Armory, Jas Kerr & Co. 54 King William St, E.C. The right frame is marked B.L.693 and ADAMS PAT, 39,693.
This 6 shot revolver is chambered for the standard British .450CF cartridge and has a 4½” barrel. The upper right frame is stamped with the South African registration number L3610. Underside of barrel, loading gate and cylinder marked with serial number 1918. There are London proof marks on barrel and cylinder but no proofmarks visible on the frame.
The revolver is cased in it's original oak case with correct London Armory trade label and accoutrements include cleaning rod and glass oil bottle. The label on the oil bottle reads ‘Young’s Celebrated Extra Refined Oil; For gun and rifle locks; Will not corrode’.
An identical revolver is pictured in the book Adams' Revolvers. The text says that no features of the revolver appear to be covered in the patents of any of either Robert or John Adams. It also indicates James Kerr took over the London Armoury name and much of the remaining stock after the company dissolved in August 1867 and had moved his address from 36 to 54 King William Street by 23 May 1868.
Adams' Revolvers, Chamberlain & Taylerson, p156-159
The Other Kerr - The Center Fire Revolver, Paul S. Lederer. The Canadian Journal of Arm Collecting, Vol.21, No.4
The Kerr-Webley-Tranter: A Revisit, Paul S. Lederer. Arms Collecting, Vol.30, No.3