Drummond light | [ From Thomas Drummond, a British naval officer. ] A very intense light, produced by turning two streams of gas, one oxygen and the other hydrogen, or coal gas, in a state of ignition, upon a ball of lime; or a stream of oxygen gas through a flame of alcohol upon a ball or disk of lime; -- called also ☞ The name is also applied sometimes to a heliostat, invented by Drummond, for rendering visible a distant point, as in geodetic surveying, by reflecting upon it a beam of light from the sun. [ 1913 Webster ] |