648 PHILOSOPHICAL TRANSACTIONS. [anNO I76g, 



part of the body ; and from the hands and fingers in such manner as to have 

 the appearance of a glove. 



XXXIX. Observation of the Immersion of Fenus on the Smi, June 3, 17 6q, 

 made at Gryphswald, by Andr. Mayer, Royal Professor. From the Latin. 

 p. 284. 



Mr. Mayer used a very good DoUond's 7-foot tube. The first exterior con- 

 tact he saw at 8*^ 4™ 35' and the interior at S*" 22*" 44' ; so that the duration of 

 the immersion was 18"" Q". During the ingress the planet's disk was greatly 

 agitated and distorted : after the middle of the immersion, her horizontal dia- 

 meter was nearly 3 times the vertical one ; and the solar light about the margins 

 of the sun and Venus seemed very yellow, and even reddish. A little before 

 the interior contact something of a fascia was seen connecting Venus with the 

 sun's margin. No satellite of Venus was seen ; nor any vestiges of an atmo- 

 sphere, which in 1761 so distinctly appeared, unless we may refer to this cause, 

 the commotion at the first immersion, and the change of colour at the margins 

 of Venus and the sun. 



XL. Observation of a Solar Eclipse June Alh 1769, at the Observatory at 

 Austhorpe, near Leeds. By J. Smeaton, F. R. S. p. 286. 



Beginning by mean time, A. m. 6^ 33™ 1* 



Middle 7 26 38 



End 8 20 ] 6 



Total duration 1 47 15 



Digits eclipsed 6° 46' 



The beginning and end of the eclipse were observed by an excellent 3-i- feet 

 treble object-glass telescope, constructed by Dollond, with the smallest mag- 

 nifier, which enlarged the diameter somewhat above 80 times. As there is no 

 defect in quantity of light from the sun, the object glass was contracted by an 

 aperture to 24- inches, and the object was perfectly sharp and distinct. The quan- 

 tity was taken by a parallel wire micrometer, upon an equatoreal apparatus, 

 which rendered it very commodious for the purpose ; by which the part of the 

 sun's diameter, remaining uneclipsed, measured at right angles to a line join- 

 ing the horns, was 889 such parts as the sun's diameter, taken the same day at 

 1-i- in the afternoon, measured between two parallels of declination, 2041. 



The estimated latitude is 53° 48'. The supposed longitude is 6"" of time west 

 of Greenvvicli ; this is deduced from its position with Wakefield, whose longi- 

 tude is set down in Maskelyne's British Mariner's Guide, as determined from an 

 observation of the transit of Venus, 1761. 



The exact knowledge at what point of the sun's circumference to look for the 



