l6'2 PHILOSOPHICAL TRANSACTIONS. [aNNO I764. 



observation, and the same day saw the island of Madeira, the body of which, 

 according to this and the former observations (which agreed exactly) he made to 

 lie 17° J 8' west of London, which differs only 18' from what it is laid down in 

 the chart. The success he met with in this first attempt gave him great satis- 

 faction, and made him continue his observations regularly to the island of St. 

 Paul's, which they made July 5. The day before he had 3 observations of the 

 distance of the moon from the sun. July the 5th, the body of the island bear- 

 ing by the azimuth compass s. 27° w. distance 6 leagues, the sky remarkably 

 clear and fine, and the ship having hardly any motion, circumstances all in his 

 favour, he took Q observations of the distance of the moon from the sun, the 

 captam and chief mate assisting him in taking the altitudes. He divided them 

 into 3 sets, and worked from the medium of every 3 ; by which he made the 

 longitude of the ship as follows, 75° 15', 75° 25', 74° 40'. The 3 observations, 

 he took the day before, made the longitude of the ship 74° 38' and 73° 32'. 

 which brought forward to the noon of July the 5th made 75° 45' and 74° 39'. 

 Taking the medium of the whole 5 sets, he made the longitude of the ship at 

 noon 75° 8' 48" east of London. Subtracting from this the difference of longi- 

 tude, the bearings and distance of the island gave = S' 37" west, he made the 

 longitude of St. Paul's 75° o' 11* east of London, and 58° O' 11" from the 

 Cape of Good Hope. By his account kept from an observation taken June the 

 18th, he made it 73° 35' east of London, and 56° 35' from the Cape, which 

 differs 1° 25' from what he makes the true longitude : most of the accounts on 

 board were between 2 and 3 degrees to the westward of his. 



LV. Of a Remarkable Meteor seen at Oxford, u4pril13, 1764. By the Rev. 

 John Swinton, B. D., F. R. S. p. 332. 



Returning home from a walk, about 8*^ 10™ p. M. looking over the houses 

 opposite to Alban-Hall, Mr. S. observed a very remarkable kind of light, 

 forming the representation of an exceedingly bright crepusculum, or expanded 

 body of vapour, which diffused itself all over the northern part of the hemis- 

 phere. About S^ 55™, not thinking of what he had seen, he threw up his sash, 

 and accidentally cast his eye towards the n. w. where he discovered a luminous 

 arch, extending itself to the opposite part of the heavens, somewhat resembling 

 an iris, but of a bright white colour. He then went out into the street, 

 traversed part of the town, and found the arch both in the n. w. and s, e. to be 

 nearly terminated by the horizon ; so that it seemed to be almost perfectly semi- 

 circular, and consequently in a manner to bisect the hemisphere, when com- 

 pletely formed. The meteor was not exactly erect, but ascended obliquely, 

 declining a little to the n. of the zenith. It was extremely narrow, in breadth 

 scarcely exceeding 2 degrees. Its edges towards the s. e. were not so well defined. 



