The study of the ancient lamp maker was de voted alone to the external form of his wares. Grace, beauty and elegance, as expressed in out lines and decorations, were his chief concern. No attempt was made to improve the light. The pale, smoky, flickering flame continued to shed its uncertain light from the massive and costly silver candelabrum of the wealthy just as it had for untold ages from the simple stone and terra cotta lamps of their ancestors. Etruscan terra cotta and bronze lamps so closely resembled those of early Greek make that a separate de scription is not required in this article. The chief characteristic, however, that distinguished the true Etruscan pottery from that of Greece is the strong coloring that was applied to the former. What was true of the art of lamp making in Greece was also true of the rest of the civilized world, for it was more than 17 cen turies after the Christian era before any real improvement was introduced in lamp construc tion.
The Inventive Age.— Prior to 1783 many lamps and illuminating appliances had been in troduced, but there was little if any improve ment in the light afforded, or marked advance ment in the construction or mechanical arrange ment of the parts designed to increase the brilliancy of the flame. The first real improve ment was the introduction of the flat, woven, ribbon-like wick, and the securing the wick in a close-fitting support. This arrangement permitted only a small surface of the wick to be exposed to the flame, and the wick being narrow the flame came in contact with the centre as readily as the outward parts and thus most of the free carbon was consumed, con sequently there was less smoke than in the old style of loose wick. M. Legers• of Paris in troduced this improvement in 1783. To this was attached for the first time a spur-wheel, which by rotating adjusted the wick, thus regu lating the flame. The same year M. Argand,* the Swiss chemist, introduced his improvement in burners, which consisted of a tubular wick attached to a tube which extended through the oil reservoir and opened into the base of the lamp, thus affording a means of centre draught, which supplied an abundance of oxygen to the flame and created sufficient heat to consume all of the carbon and so prevented the escaping of smoke. This was truly the beginning of a new era in lamp making, for the art now en tered upon what may be designated as "the inventive age of the lamp." Science and inven tion now came to the aid of the artisan. Prin ciples involving an understanding of the laws of combustion and the science of light were ap plied to the construction of illuminating devices. The result was more light and better light. Ar gand's epoch-making invention related wholly to his improved burner. His first lamps were simply huge oil reservoirs with his new burner attached to the top. He used sheet iron chim neys formed with a hood opening over the flame. The use of glass chimneys with the
Argand burner came about purely by accident. A workman in attempting to heat a bottle over the flame cracked off the bottom, and' because the glass had become too hot for him to hold he momentarily placed it over the burner. The result was suprising; the bril liancy of the flame was not only increased but the light became steady and in every way superior to that produced with a sheet iron chimney. The brilliancy of the light on the top of the huge reservoir made a wide shadow. To overcome this was a problem that was finally solved by a German lamp-maker, who produced a model in which the burner was secured to the end of a long neck or rostrum, very much like the present so-called German student lamp. The removing of the light away from the great reservoir not only reduced the shadow but afforded a more ready means of supplying the oil to the wick uniformly. In 1800 Carcel introduced his ingenious lamp which was provided wih a clock-work device, which operated a small pump, raising the oil from the base of the lamp to the wick-holder, thus keeping the wick uniformly submerged in the oil. This contrivance was too costly to come into general use, and was confined mostly to lamps used in halls and large rooms. Many lamps were offered by makers that were de signed to burn crude, heavy whale oil, and others in which lard oil was consumed. Lard oil lamps were inconvenient in cold weather, for the oil would become solid. To overcome this several devices were invented. Perhaps the most successful was the lamp with a copper tube, the upper end of which was between two wick tubes, while the lower end passed through the oil to the bottom of the lamp. Copper being a good conductor of heat, the oil was thus kept in a liquid state while the lamp was burning. For many years lard oil was the only illuminant used in the great lamps of the lighthouses of the world. It was not until after 1880 that burners for lighthouse lamps had been constructed that would satisfactorily consume kerosene oil. Up to about 1800 but few small, portable lamps had been made. Nearly all the appliances so far introduced for domestic illumination were large, so-called, . table lamps, and mural lamps. English manu facturers first made small hand lamps of tin, brass and pewter. These were mostly lard or whale oil burners, with a single wick tube. In the whale oil lamps the wick tube was round, in the lard oil lamps the flat, woven ribbon wick was used, the wick being moved up and down in the lard oil lamps by a spur-wheel. In the whale oil lamps a small aperture in the upper part of the wick tube was provided, through which °a prick" could be inserted by which the wick was pricked up or down. In the large and important field of research and experiment in domestic illumination, American genius and skill very early took a prominent part.