588 PHILOSOPHICAL TRANSACTIONS. [aNNO 17681 



light about the exterior limb of the planet; this light, during all the time of its 

 contirmance, appeared rather reddish, and in all respects like irregular refracted 

 light. After Venus was wholly entered on the sun, he saw a faint ring sur- 

 rounding her. After Venus was wholly entered on the sun, and her exterior 

 limb was near one of her semidiameters distant from the sun's circumference, 

 Mr. Nairne saw a faint light round the planet, rather brighter and whiter than 

 the body of the sun. 



Fortunately, the weather was as favourable for the observation of the sun's 

 eclipse the next morning, as it had been the evening before for that of the in- 

 gress of Venus on the sun; which is of the more consequence, as the comparison 

 of it with the observations which may be made of it in the northern and eastern 

 parts of the world will serve to settle the longitudes of those places, and conse- 

 quently render the observations which may be made there of the transit more 

 useful and valuable. Mr. M. observed the beginning of the eclipse at 18"^ 38™ 

 54', and the end at 20** 23™ 30' apparent time, with the 2-feet reflector, using 

 the magnifying power QO times. And at IQ** 29™ 3 P apparent time, he observed 

 the greatest eclipse, at which time he found the remaining lucid parts of the 

 sun 15' 15" with DoUond's micrometer, assuming the horizontal diameter of the 

 sun 31' 31", whence the value of the scale of the micrometer was determined 

 for the present purpose. Hence the eclipsed parts of the sun were 16' 16" or 

 6° 1 1',62 on the northern part of his disk. 



Mr. Kitchens observed the beginning of the eclipse with a 34^-feet achromatic 

 telescope magnifying 1 50 times (the same with which Mr. Dollond observed the 

 contacts of Venus), at 18'' 38™ 59% and the end of the eclipse with the 6-feet 

 reflector with the magnifying power 90, at 20'' 23"" 35' apparent time. And 

 Mr. Samuel Dunn observed the beginning of the eclipse at 18'' 39™ 9% and the 

 end at 20'' 23™ 33' with the other 34-feet achromatic telescope, magnifying 140 

 times, the same with which he observed the contacts of Venus. Several ine- 

 qualities in the moon's circumference, seen on the sun's disk during the eclipse, 

 were distinctly discerned by all of them, the air being very clear, and the ob- 

 jects steady. 



The whole series of measures of the Apparent time. Lucid parts. 



lucid parts, which Mr. M. took with the 19' 22"' 13^ 15' 40".5 



achromatic object glass micrometer ap- ofi o 1^ on o 



plied to the 2-feet telescope, was as au- gg 26 15 15 .6 



nexed. 30 14 15 14 .5 



31 44 15 16 .4 



32 SO 15 16 .4 



33 19 15 19 .8 



34 28 15 25 .4 



36 19 15 35 .9 



37 S6 15 49 .1 



END OF THE FIFTY-EIGHTH VOLUME OF THE ORIGINAL. 



