Meteorological observations and essays / By John Dalton.

  • John Dalton
Date:
1834
Catalogue details

Licence: Public Domain Mark

Credit: Meteorological observations and essays / By John Dalton. Source: Wellcome Collection.

    96/280 (page 70)
    M, Variation. 35 P. M. 25° 5’W.a grand horizontal arch, altitude 6°. —— 25 25 — streamers to 30° past the zenith. 48 —— 25 5 — bright eastward. —— 25 5 — streamers faint. 25 5 — dense light north; rare above. 25 10 — ditto. 24 55 — bright westward. 24 55 — a fine, perfect, horizontal arch. 20 24 55 — altitude of its upper edge 30°. 30 24 30 — streamers up to the zenith. 35 ——— 24 35 — dispersed, and not so high. 45 24 58 — faint light; brightest eastward. 52 —— 24 45 — dull light. —— 24 42 — dull light; haze below. — —_— fas} ODomw~mpnmrpvpnn Don HOO OH DO DO OW: — nr 10 24 42 — haze risen; light fainter. 10 15 —— —— — clouds risen; light almost vanished. 10 30 —— 24 45 — clouds more risen. 11 15 —— 24 45 — several small clouds cover the hemisphere. 8 OA.M. 24 54 There were several fine, perfect, concentric arches northward, during most of the time.-—At 8h 48m one fine arch, the altitude of its under edge 10°. At 8h 55m two perfect arches, altitude of the higher 12°, with a fine edge. At 9h several concentric arches, one with a fine edge, altitude 11°. At 9h 5m one of the upper arches with a very bright edge, its altitude 13°; the bases of the streamers composing it of very dense light, and rare above. At 9h 10m its altitude 13 or 14°.—At 9h 15m the upper edge of the large horizontal light seems now as well defined as that of a rainbow, its altitude 47°, and that of the under edge 10°. At 9h 20m altitude of upper edge 30°. The arches were all at right angles to the magnetic meridian, and the beams had their usual convergency.—At one time several small streamers formed a corone upon the magnetic meridian, the centre of which was determined by a good observation to be 72° from the south. The sky was free from clouds till the last.