50 Years Ago

While the causes of clear air turbulence remain obscure, it is clear that it is often associated with temperature gradients in the atmosphere. Recent work at Oxford and Reading Universities may offer a way of detecting the gradients, and, by inference, the turbulence. If this can be detected far enough ahead of aircraft, evasive action can be taken ... Dr J. T. Houghton of the Clarendon Laboratory at Oxford and ... Dr S. D. Smith of the Department of Physics at Reading ... have developed a radiometer which detects the infra-red radiation from carbon dioxide in the atmosphere ... intended to provide a world-wide survey of the temperature of the atmosphere up to about 30 miles. At different heights in the atmosphere, the carbon dioxide band occurs at different wavelengths, so that by choosing a certain wavelength a certain height can be studied by the instrument in the orbiting satellite.

From Nature 8 July 1967

100 Years Ago

Efficient protection of the eyes from glare is a subject of considerable importance at the present time, but unfortunately a great deal of misconception has arisen in regard to it. Most glare protectors are designed for conditions of unusually strong illumination; generally speaking, for daylight ... A great deal of experimental work has been done recently on the physiological effects of ultra-violet radiation in the eye, a quartz-mercury lamp being used as a source, which is especially rich in its emission of the shorter wave-lengths. The results ... are that with long-continued exposure serious harm may result from the absorption of these shorter waves ... but with low intensities of radiation regular exposures produce no permanent effect.

From Nature 5 July 1917 Footnote 1