Abstract
THE ECLIPSE OF APRIL, 1893.—M. Bigourdan communicates to Comptes Rendus for May 23 (No. 21) a brief preliminary account of his observations made during this total eclipse of the sun. The station he occupied was Joal (approximately Longitude 1h. 16m. 38s. E. of Paris, and Latitude 14° 9′ 25″N) and the observations were made from the Observatory erected by the Expedition of the Bureau des Longitudes. With an eyepiece magnifying 190 times he observed several occultations of solar spots by the moon, and in about fifteen cases he noticed the phenomenon that is equivalent to that seen in observations of the Transit of Venus and known as the black drop. It was produced, he says, not only at the contact of large spots, but at the point of contact of small ones, and even of the simple filaments forming the penumbræ of spots. M. Bigourdan also made a special look for the phenomena known as Baily's beads, sometimes seen when the sun has been reduced to a very fine crescent by the advance of the lunar disc, but from all accounts he seems to have been unable to see any trace of them. A search round the sun for an intra-Mercurial planet, with a telescope giving a field of 25′, was also made, but with no satisfactory result, since he says that his instrument was not suited for that purpose: the negative result thus obtained affords no argument against the existence of such a body. The duration of totality lasted exactly 4m. 1s.
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Our Astronomical Column. Nature 48, 111–112 (1893). https://doi.org/10.1038/048111a0
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DOI: https://doi.org/10.1038/048111a0