100 YEARS AGO

In connection with the recent correspondence in these columns on luminous phenomena observed on mountains, it is interesting to direct attention to a very remarkable series of observations of electrical storms on Pike's Peak, Colorado, contained in vol. xxii. of the Annals of the Astronomical Observatory of Harvard College, and described in NATURE⃛ . Luminous jets appeared very often along the telegraph wires for the length of an eighth of a mile, and the anemometer cups looked like revolving balls of fire. Upon touching the anemometer under these conditions, an observer found “his hands instantly become aflame. On raising them and spreading his fingers, each of them became tipped with one or more cones of light nearly three inches in length.”

From Nature 3 June 1897.

50 YEARS AGO

Prof. J. Kaplan proposes the name ‘active oxygen’ for certain luminous phenomena observed by him “just as the name active nitrogen was given to similar phenomena in nitrogen”. I write to point out that this is not historically correct. ⃛ The chemical activity referred to was the combination with metals such as sodium and mercury, to form nitrides, and with organic materials to form cyanogen compounds. Striking luminous phenomena often accompany these chemical actions, but it is wrong to regard these effects as the essence of the matter. As a matter of fact, the number of nitrogen molecules which emit a photon of afterglow light is very small compared with the number which become chemically active. For this reason, I do not think that the afterglow should be regarded as the essential phenomenon of active nitrogen, and I do not think that in the present state of knowledge the term ‘active oxygen’ should be applied by analogy, when only luminous phenomena are so far known to be involved. This would only cause confusion.

From Nature 7 June 1947.

Many more abstracts like these can be found in A Bedside Nature: Genius and Eccentricity in Science, 1869-1953, a 266-page book edited by Walter Gratzer. Contact David Plant (e-mail: subscriptions@nature.com).