This view of its notice was corrected by Sir H.Davy (in 1809), who gave it the present name.

In 1840-41, this gas vas employed for accelerating the operation of light upon the iodized Daguerreotype plate.

John Goddard, Wolcott & Johnson, Claudet, Draper, Morse and others, were among the first made acquainted with its use.

Count Rumford, Ritter, Scheele, Seebert and others, experimented with chlorine in regard to its effect when exposed to the action of light in combination with silver.

In 1845, M.Edward Becquerel announced that he had "been successful in obtaining, by the agency of solar radiations, distinct impressions, of the colors of nature." On the 4th of March, 1851, Neipce, St.Victor, a former partner of DAGUERRE, announced that he had produced "all the colors by using a bath of bichloride of copper, and that a similar phenomenon occurs with all salts of copper, mixed with chlorine." Preparation .-- This is easily accomplished by putting about two parts of hydrochloric (muriatic) acid on one of powdered black oxide of manganese, and heating it gradually in a flask or retort, to which may be adapted a bent glass tube.