Also check out " The British Shotgun Vol.2 1871 to 1890" by Crudgington & Baker, "Shotguns & Gunsmiths" by Boothroyd,'Heyday of the British Shotgun" by Baker, not to mention " History of W & C Scott' by Crawford & Whatley. For a succinct note on how Birmingham made guns were sold under their own names by many of the leading London names, not to mention provincial gunsmiths, see p.162 of 'Vintage Guns for the Modern Shot" by Hadoke. Crudgington & Baker are particularly good on patents/new designs, as is Greener in The Modern Shotgun, but he puts his own designs on a pinnacle as he was writing contemporaneously and had his own products to sell.