ḤANUKKAH LAMP — (also known as ḥanukkiyyah and Ḥanukkah menorah). The central ritual of the eight day Festival of Ḥanukkah is the kindling of a lamp that has receptacles for eight lights, one for each night. A ninth receptacle, called the servitor or shammash,… … Encyclopedia of Judaism
British absolute block signalling — The principle of the British absolute block system of railway signalling is to facilitate the safe operation of a railway by preventing more than one train from occupying a defined section of route at the same time. This system is used on double… … Wikipedia
Metal-halide lamp — A metal halide gas discharge lighting system provides illumination for a college baseball game at Olsen Field in College Station, Texas, United States. Note the various colors of the lights as they warm up. Metal halide lamps, a member of the… … Wikipedia
Plasma lamp — Plasma lamps (also variously plasma globes, balls, domes, spheres, or orbs) are novelty items which were most popular in the 1980s. The plasma lamp was invented by Nikola Tesla after his experimentation with high frequency currents in an… … Wikipedia
Fluorescent lamp — A fluorescent lamp or fluorescent tube is a gas discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light.Unlike… … Wikipedia
Deuterium arc lamp — A deuterium arc lamp (or simply deuterium lamp) is a low pressure gas discharge light source often used in spectroscopy when a continuous spectrum in the ultraviolet region is needed. Contents 1 Principle of operation 2 Deuterium lamp spectra 3… … Wikipedia
Shabbat lamp — A Shabbat lamp is a special lamp that has movable parts to expose or block out its light so it can be turned on or off while its power physically remains on. This enables the lamp to be used by Shabbat observant Jews to make a room dark or light… … Wikipedia
incandescent lamp — a lamp that emits light due to the glowing of a heated material, esp. the common device in which a tungsten filament enclosed within an evacuated glass bulb is rendered luminous by the passage of an electric current through it. Cf. fluorescent… … Universalium
Jack lamp — Jack Jack (j[a^]k), n. [F. Jacques James, L. Jacobus, Gr. ?, Heb. Ya aq[=o]b Jacob; prop., seizing by the heel; hence, a supplanter. Cf. {Jacobite}, {Jockey}.] [1913 Webster] 1. A familiar nickname of, or substitute for, John. [1913 Webster] You… … The Collaborative International Dictionary of English
Jack block — Jack Jack (j[a^]k), n. [F. Jacques James, L. Jacobus, Gr. ?, Heb. Ya aq[=o]b Jacob; prop., seizing by the heel; hence, a supplanter. Cf. {Jacobite}, {Jockey}.] [1913 Webster] 1. A familiar nickname of, or substitute for, John. [1913 Webster] You… … The Collaborative International Dictionary of English
