Cooper Hewitt mercury arc lamp
Date: 1915-1925
Inventory Number: DPW0103a
Classification: Lamp
Subject:
Maker: Cooper Hewitt Electric Company (1902 - 1919)
Maker: General Electric Vapor Lamp Company (1919 - 1939)
Maker: General Electric Company (1892-present)
Cultural Region:
Place of Origin:
Dimensions:
135.9 x 24.4 x 21.6 cm (53 1/2 x 9 5/8 x 8 1/2 in.)
Material:
Description:
A discharge lamp consisting of a long rectangular mount in reflecting white with a concave (cylinder section) shape with clamps for holding a tube. Additional wire hooks and loop on the back for further securing the lamp. Behind the mount is a ballast for producing the high voltage and current needed for the lamp. Ballast has removable cover and chain for hanging.
Signedplate on side: DIRECT CURRENT / COOPER HEWITT LAMP. / UNDER PATENTS OF / COOPER HEWITT ELEC. CO. AND GENERAL ELECTRIC CO. / PAT'D JAN. 11,'11 FEB. 23, '13 AUG. 12, '13 NOV. 25, '13 MAR. 24, '14 SEPT. 15, '14 OCT. 26, '15 / OTHER PATENTS PENDING / FOR P LAMP / TYPE EDC SPEC. 1B AMPS 35 / SINGLE ON 100 TO 125 VOLTS / COOPER HEWITT ELEC. CO. / HOBOKEN, N.J., U.S.A.
FunctionThe Cooper Hewitt lamp was invented in 1901 by Peter Cooper Hewitt of New York City. It was the first successful discharge lamp, emitting light from an electrical arc extending between electrodes in a low pressure mercury vapor. The lamp's tube contained a significant amount of liquid mercury, which evaporated during use to maintain the conduction of electricity.
The main advantage of the lamp over incandescent bulbs was its much higher efficiency (advertised as over eight times more efficient). However, the mercury arc emitted a very unnatural blue light, which limited its appeal for household illumination. Initially, it had a market in large industrial spaces (which gradually turned to other systems after the 1910s), and later it remained very popular for specialized applications. Particularly in the printing and photography industry it was the preferred lamp as its emitted wavelengths were especially chemically reactive.
It continued to be produced as late as 1965.
The main advantage of the lamp over incandescent bulbs was its much higher efficiency (advertised as over eight times more efficient). However, the mercury arc emitted a very unnatural blue light, which limited its appeal for household illumination. Initially, it had a market in large industrial spaces (which gradually turned to other systems after the 1910s), and later it remained very popular for specialized applications. Particularly in the printing and photography industry it was the preferred lamp as its emitted wavelengths were especially chemically reactive.
It continued to be produced as late as 1965.