VOL. XLV.] PHILOSOPHICAL TRANSACTIONS. 503 



meter of the moon, when she was on the sun; which he found = 29' 47-^". 

 He measured also the apparent vertical diameter of the sun at noon; which he 

 found = 31' 40". 



The eclipse was so nearly annular, that, at the nearest approach, the cusps 

 seemed to want about J- of the moon's circumference to be joined; yet a brown 

 light was plainly observed to proceed or stretch along the circumference of the 

 moon, from each of the cusps, about ^ of the whole distance of the cusps from 

 each cusp; and there remained about -^ of the whole distance of the cusps not 

 enlightened by this brown light; so that they were for some time in suspense 

 whether they were to have the eclipse annular. Mr. S. observed, at the extre- 

 mity of this brown light, which came from the western cusp, a larger quantity 

 of light than at any other place, which at first surprised him ; but afterwards 

 he imagined it must have proceeded from some cavity or valley made by two ad- 

 joining mountains on the edge or limb of the moon. He had often formerly 

 observed mountains on the circumference of the moon, more or less every where 

 round it, but never saw them so plain as during the time of this eclipse; for the 

 air was exceedingly clear, and free of all agitation, though it blew a perfect hur- 

 ricane of wind, which began about the middle of the eclipse; and he remembered 

 that in the annular eclipse of the sun in the year 1737, it did the same. The 

 mountainous inequalities on the southern limb of the moon were particularly 

 remarkable; in some parts mountains and valleys alternately; others extended a 

 CQUsiderable way along the circumference, and ended almost perpendicularly like 

 a precipice. Lord Morton was able to see them very easily through his small 

 reflector. 



A little after the middle of the eclipse, some clouds, that seemed stationary 

 below the sun, appeared tinged on their upper extremities with all the colours of 

 the rainbow. 



During the greatest darkness, some people, who were in the garden adjoining 

 to the castle, saw a star to the east of the sun; which, when they afterwards 

 pointed to the place where they had seen it, showed that it must have been the 

 planet Venus. This star, they were afterwards told, was seen also at Edinburgh, 

 and other places, by a great number of people ; but he did not hear of any other 

 stars being seen. The darkness was not great, but the sky appeared of a faint 

 languid colour. What is pretty remarkable, Mr. le Monnier found, that when 

 he looked at the sun with his naked eyes during the middle of the eclipse, he 

 could observe nothing on the sun, but saw the sun full, though faint in his light. 

 This, Mr. S. imagines may be owing to his being short-sighted. 



Mr. S. observed also, about the middle of the eclipse, a remarkable large spot 

 of light, of an irregular figure, and of a considerable brightness, about 7' or 8' 

 within the limb of the moon next the western cusp. He thought he lost this 

 VOL. IX. 4 G 



