1907 16 Feb. 14/2 The osmium lamp..was expensive to start with, and could be used only in the pendent position.
1952 H. Hewitt iv. 34 Whilst further developments such as the Nernst lamp, the osmium lamp and the tantalum lamp were all of technical interest, it was not until the adoption of the tungsten filament by Coolidge in 1909 that there was any considerable advance towards more efficient electric lamps.