378 Cambridge Philosophical Society* 



most clearly visible when the eye had had some rest. On applying 

 it then to the glass, it was most easily distinguished. 



W The observers at Dr. Van Beek's house saw nothing of this 

 singular phenomenon. 



M Some observers state, that in former transits a coloured lighter 

 ring seemed to surround the orb of Mercury on the Sun's disc. 

 According to Plantade, an appearance of the sort was seen at the 

 transit of 1736. Flaugergues saw the same in May 1786, in Nov. 

 1789 and 1799. He calls it an illuminated ring, un anneav lumineux. 

 Nothing, however, of the kind is mentioned in Delambre's account 

 of the transit of 1799, nor in that of Messier of that of 1786. Pros- 

 perin and Ferner, however, speak of it as observed during the transit 

 of 1786. But the most circumstantial account of the phenomenon 

 is that of Harding and Schroder, during the transit of 1799. They 

 describe it exactly as we saw it, both with the 42-inch and 6-feet 

 telescopes. A nebulous ring of a darker tinge, approaching to the 

 violet. colour, appeared to surround Mercury s disc. Near the planet 

 the colour was darkest. Now, what we saw, and Schroder and 

 Harding saw, is exactly the reverse of what is mentioned by Plan- 

 tade and Prosperin. They talk of a luminous ring; we saw, or at 

 least think we saw, a darker, more deeply-coloured zone surrounding 

 Mercury. Ljungberg saw also a dark nebulous ring round Mer- 

 cury, at Copenhagen, in 1802*. 



V. Occupation of Saturn by the Moon. Observed at Utrecht, 

 by Dr. Moll and Mr. G. R. Fockens, 8th of May, 1832. 



The same phenomenon was observed at Leyden, by Professor 

 Uylenbroek and Mr. Kaiser. 



VI. Remarks on the fifth Catalogue of Double Stars, commu- 

 nicated to the Society, June 7th, 1832. By Sir J. F. W. Herschel. 



VII. Stars observed with the Moon at the Royal Observatory, 

 Greenwich, in the months of October and November, 1832. 



VIII. Stars observed with the Moon, at the Cambridge Obser- 

 vatory, in November and December 1832. 



December 10, at 12 h 21 m 53 s *86 Cambridge sidereal time, or 

 19 u l m 32 s, 8 Greenwich mean solar time, I Cancri disappeared at 

 the Moon's bright limb. The limb was uneven, and the star seemed 

 to run along one long mountain slope before it disappeared. The 

 time is uncertain two or three seconds. 



There was laid on the table, amongst other presents, a MS. copy 

 of Dr. Halley's astronomical observations made at the Royal Obser- 

 vatory at Greenwich, copied from the originals by order of the Lords 

 Commissioners of the Admiralty, and by them presented to the 

 Society. 



PHILOSOPHICAL SOCIETY OF CAMBRIDGE. 



March 11. — A Memoir by theMarchese Spineto was read, con- 

 taining objections to the chronological system of Sir Isaac Newton ; 

 and reasons for preferring the more extended chronology, which is 



* Zach. Monatl. Corresp. vol. viii. 1803, p. 335. 



