Christies South Kensington London, Mechanical Music And technical Apparatus, Lot 14, was an early Swan carbon filament lamp. I actually had this in my hands complete with its holder threaded 1/8th inch BSP to screw into existing gas bracket. It was a two loop and hook fitting with one loop missing, broken off at glass, fillament O,K, Estimated ?200-400 sold at ?85.
Bob Smallbone Bognor Regis U.K.