The Year-Book of Facts in Science and Art
Exhibiting the Most Important discoveries and Improvements of the past year,
in mechanics and the useful arts; natural philosophy; electricity; chemistry; zoology and biology; geology and geography; meteorology and astronomy.
By John Timbs,
editor of "the Arcana of Science and Art."
London:
David Bogue, Fleet Street,
MDCCCXLIX (1849)There was a magnificent display of Aurora Borealis, on the evening of Sunday, Feb. 20, 1848: from numerous descriptions, we find selected, in the Athenæum, the following letter of Mr. Temple Chevallier. — "In the course of a fine display of Aurora Borealis at Durham, on the 20th of February, an auroral arch was observed of a very definite character. At 8h. 16m., Greenwich mean time, an arch of bright light, having a uniform breadth of about 2°, suddenly arose near the horizon in the N.E., and instantly spread across the whole sky. It passed a little eastward and southward of the stars of the Great Bear, directly across Capella, and a little west of the Pleiades. From these data it appears that the direction of the arch was very nearly that of a vertical circle, passing over the zenith of Durham, and, as usual, very nearly at right angles to the magnetic meridian. The arch was not traced to its western termination. Its duration was less than a minute. It is to be hoped that observations may have been made of the same arch in other places, so that its height above the earth's surface may be calculated. The barometer was remarkably low at the time, 28.421 inches; and the thermometer 39°5. The place of observation was 247 feet above the level of the sea. The latitude of Durham is 54°46’ 6", and its longitude 6' 18" west of Greenwich.
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