1851 Great Exhibition: Official Catalogue: Class VIII.: George Gibbs
215. GIBBS, GEORGE, Clare Street, Bristol — Inventor and Manufacturer.
Improved registered double-barrel gun, in which missing fire is prevented in wet or damp weather, by the introduction of an iron cover to shut over the cap and nipple; the cover is raised by the action of the hammer falling upon the percussion cap, which it fires in the usual way, and is moveable, so that the gun may be used with or without it.