The Mount Whitney Expedition | Nature

EXPERIMENTS at the Alleghany Observatory in 1879 and 1880, upon the selective absorption of the solar rays by the earth's atmosphere, having made it probable that the amount of heat the sun

sends us (the solar constant) had been under-estimated by the methods of previous observers, and that conclusions of importance connected with the temperature of the planet remained to be

drawn, it became desirable to verify these results, obtained near the sea-level, by direct simultaneous observations at the base and summit of a very high mountain.

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