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