High pressure mercury vapour lamp
circa 1951
Osram high pressure mercury vapour lamp
circa 1945
Osram mercury vapour lamp
circa 1940
mercury vapour lamp
mercury vapour lamp
circa 1975
MA/V mercury vapour lamp
circa 1946
mercury/tungsten light bulb
circa 1970
Mercury vapour electric lamp
1900
Mercury vapour electric lamp made by Whouse Cooper Hewitt
1915