VOL. LtX.] PHILOSOPHICAL TRANSACTIONS. 631 



From the preceding observations and calculations, it appears that the latitude 

 of the observatory was 40° 9' 56* north, and its longitude S"* 1" 34* west of 

 Greenwich. 



XLII. Observations of the Transit of Fenus over the Sun, June 3, 17 69, Tuade 

 in Sweden, and communicated to the R. S. by Mr. Peter fVargentin, F. R. S. 

 and Sec. to the Royal ./Academy of Sciences at Stockholm. From the Latin. 

 p. 327. 



The Royal Academy of Sciences of Stockholm sent several astronomers to 

 different parts of the Swedish dominions, to make observations on this transit 

 of Venus, &c. viz. Mr. Mallet, royal astronomical observer at Upsal, went to 

 the villa called Pello, being the northern extremity of the terrestrial meridian 

 arc measured by the French astronomers in the year 1736. Mr. Planman, pro- 

 fessor of Natural Philosophy in the academy of Aboen, returned to Cajane- 

 burg, a town situated on the confines of Finland and Lapland, where he before 

 observed the transit of 1761. A third observer, Mr. Hellant, of the town of 

 Tornea, an experienced and skilful observer, was to make his observations at 

 that place. Besides these, 5 other gentlemen were appointed to make the obser- 

 vations at Upsal ; viz. Mr. Stroemer, emeritus professor of astronomy ; Mr. 

 Melander, professor of astronomy ; Mr. Bergman, professor of chemistry ; Mr. 

 Prosperin, deputy astronomical observer ; and Mr. Salenius, master of philoso- 

 phy. In addition to these, three other persons attended to take the observations 

 at Stockholm ; viz. Mr. Ferner, the royal chancellor, and formerly astronomy 

 professor ; Mr. Wilcke, lecturer on experimental physics ; and Mr. Wargentin 

 himself. 



The 2 gentlemen, Mr. Mallet and Mr. Hellant, were prevented from fulfilling 

 their mission, by the intervention of clouds and bad weather. But Mr. Plan- 

 man was rather more fortunate; for though the sun was obscured by clouds that 

 morning, as well as the day before, yet it afterwards cleared up, when at 9'' 8™ he 

 had a sight of the sun, when he perceived that -J- part of the planet's diameter 

 had entered on the sun's disk. And at Q^ 20^" 45'-J- it was totally immerged, 

 when he saw suddenly break off the fasciola, which had hitherto connected the 

 margins of the sun and Venus, and the body of the planet appeared completely 

 surrounded by the sun's light. Very soon after this the sky became quite ob- 

 scured with clouds, till at 3*' il"" afternoon he had another glimpse of the sun, 

 when he found the planet about ^ part emerged ; after which he watched atten- 

 tively for the final or exterior contact, which happened at S*" 32"" 27', which he 

 saw with a good tube of 20 feet. The next day, June 4, the sky being clear, 

 Mr. Planman observed the sun's eclipse, viz. the beginning at 9'' O" 43», and the 

 end at ll^O"" o-k- The latitude of the place, Cajaneburg, is 64° 13'i, and its 



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