Electric Conductivity of the Atmosphere

Abstract

ONE of the Notes in NATURE of November 25 (p. 351) begins with the following sentence:—“The theory that the upper layers of the atmosphere are ionised and therefore conduct electricity, first enunciated by the late Prof. FitzGerald in 1893,...” It is a good rule, to which I have always hitherto adhered, not to raise questions of priority, but in this particular case a point of general interest in scientific history is involved, and a claim made which postpones the enunciation of a fruitful idea by six years. In the paper presented to the Royal Society in May, 1887 (Proc. Roy. Soc., vol. xlii., p. 371), I proved by experiment that the gas in a vessel through which an electric discharge passed became a conductor even in regions of the vessel remote from the discharge, and at the end of the paper the application of this result to the conductivity of the regions of the atmosphere affected by thunderstorms and auroræ is quite clearly expressed.