Heat a ball of lime in a hydrogen-oxygen flame, and what do you get? Limelight! This very intense light source was used for lighting plays (hence the modern usage of the word), but it also was the source for the record distance, for a time, over which man-made light was observed. In the late nineteenth century, a lime-light signal was observed between Antrim, Ireland and Ben Lomond, Scotland, a distance of ninety five miles. Not only was lime-light used for signalling and in theatre, but it also played a role in the American civil war. Union forces equipped ships and batteries with lime-lights, which were also called "Drummond lights", after their inventor, Lt. Thomas Drummond, of the Royal Engineers. Mr. Beal does a very nice job with the history of the lime-light, but chemists might also want to read an article that the Journal of Chemical Education published on this historical technology, "A Reacquaintance with the Limelight", by M. B Hocking and M. L. Lambert, J. Chem. Educ. 64, 306-310 (1987).