long-time burning oil

long-time burning oil

[′lȯŋ ‚tīm ¦bərn·iŋ ‚ȯil]
(materials)
Carefully refined kerosine used in railway semaphore signal lamps; heavy ends are removed so that the oil will burn without charring the wick.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.