A Third Colour for Railway Signals.
Most people who travel by rail are aware that at night two colours are used in signal lamps, red for "danger" and green for "safety" ; it may how- ever be news to learn that a third colour is being introduced for "distant" signals by British railway com- panies. Under the old system a red. light was a "warning" on a "distant"
signal and a "stop" on a "home" signal, and this entailed, not only a risk of unnecessary delay but even a danger of over-running a "'home" by failing to observe its corresponding "distant" signal. It was found very difficult to produce a glass with a colour distinguishable from red and green, and also from any stray white or yellowish lights which might be seen from the footplate. After some years of research suitable glass has been, produced by a noted British firm, and is now being supplied to the railway companies, and is in actual use. Its colour is a mod- erately deep orange, which is as nearly as possiblo the ideal. In foggy wea- ther the colour tends to approach the appearance of the red signal, so that there is no possibility of its being, mis- taken for the green. The choice of the third colour for signals has, moreover, called for im- portant scientific research on colour specification and colour measurement. Colour is a subject which received special attention at the meetings of the Optical Convention, recently held at the Imperial College of Science, Lon- don, and the instruments which have been evolved for dealing with these problems were exhibited by the optical firms who make them. Railway travel has already the re- putation of being one of the safest forms of locomotion, but the coopera- tion of science and industry has thus provided an additional safeguard and eliminated still further the possibility of human error.
Little Molly was the daughter of a Baptist preacher, but she had been in- vited by a little friend to go with her to the Methodist Sunday school next day. Her father asked her if she didn't think she ought to go to her own Sun- day school. "Of course, Daddy," she replied, "but, please. Daddy, if you let me go I'll promise not to believe a word they say."