21 March – 21 June 2016 in Florence, Rome, Naples, Palermo, Padua

The Eclipse of the sun.

eclipse_sunThe accounts of some of the astronomical observers, on the 22nd ult., at Gibraltar, Cadiz, Seville, and Oran, on the African coast, where the eclipse was total, were briefly noticed in our last. We are indebted to Captain T. R. Lethbridge, commanding H.M.S. Trafalgar, and to Mr. Eaton Wallace Petley, navigating midshipman, for the communication of several diagrams, which we
have engraved, and,of a few notes, to record what they witnessed from the stern of that ship, moored alongside the New Mole at Gibraltar. Their notes are as follows :— “At the commencement of the first contact we did not get the exact time, on account of a cloud passing over ; but the time of contact of the first spot on the sun with the moon was 23h. 9m. 56s., Greenwich mean time. The second spot was obscured by cloud. Just before the totality (we may say 3 min.) we observed three bright rays of light shoot out from the S.W. quarter of the sun (as shown in fig. A), which lasted almost 30 sec., and did not appear again until after the totality, when only one ray darted out from the south quarter, as shown in fig. C. During the totality we observed rays of bright light dart from the sun as in fig. 13, but observed no red flame. The totality lasted 1m. 25s., during which time the wind lulled considerably; the barometer at 29-93, falling steadily. and thermometer at 61 ; wind N.W., force 3. We observed three stars, Venus, Mercury, and Saturn. At 21m. 33s. after the totality the first spot on the sun appeared ; at 25m. 30s., the second spot appeared ; and at 1h. 25m. 40s. from the time of totality the eclipse ended. The time between the contact of the first spot with the moon and the totality was 1h. 6m. 30s. ; the time of the totality was lm. 55s. ; the time between the totality and the reappearance of the first spot was 21m. 33s.; the time from the totality to the reappearance of the second spot, was 25m. 308. The rays of light, as shown in fig. A, darted out suddenly, one after the other, for a certain distance; and, after two seconds interval, as suddenly prolonged themselves, until they had the appearance of those shown in the diagram fig. A, but after an interval of thirty seconds they disappeared. Their
colour was bright red. With reference to fig. B, it was remarked that, during the totality, a bright ray of light appeared to radiate from the centre around the circumference of the moon, but varying in length. The other, fig. 0, shows how the light shot out suddenly to the extent shown in the Engraving ; this phenomenon lasted about thirty seconds. Some of our readers are aware that the most interesting subject of inquiry to be determined by these observations of the eclipse was the nature of the corona, or “glory,” of white light encircling the globe of the sun, and visible only when that globe itself is hidden. This question is, whether this light comes from a luminous gas, an atmosphere of the sun, or from solid matter in a state of white heat. The bright red prominences, flame-like or cloud-like, seen around the disc of the sun during an eclipse are known to belong to an envelope of glowing gas which surrounds the solar globe.

The illustrated London news, 1871, vol. 58, n. 1632

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