vol.. XVII.] PHILOSOPHICAL TRANSACTIONS, 431 



Buried. Buried. 



Males 1 1828 Males 1 1 1 74. 



Females 1078 1 Females 10286. 



In all 22609 In all 21460. 



END OP VOLUME SIXTEENTH OP THE OBIGINAL. 



An Account of an Observation of an Eclipse of the Moon, observed at Moscow 

 in Russia, on April 5, 1 688, compared with the same observed at Leipsic ,• by 

 which the Longitude of the former Place is ascertained ; with the Latitude of 

 several principal Places in the Empire of Russia. N° 192, p. 433. Fbl, XFH, 

 The Royal Society being desirous to contribute what they can to the recti- 

 fying of geography, and determining the longitudes of places, among others 

 recommended the procuring an eclipse to be observed at Moscow, to an eminent 

 merchant trading there ; at whose instance one Mr. Timmerman, a mathemati- 

 cian at the place, returned the following account. 



April 5, 1688, half a quarter of an hour after 7 in the evening, the moon 

 arose clear, without any sign of eclipse ; at 7\h. the moon went into a thick 

 cloud, but was again clear at 7h. 38m. when the under side of the body of the 

 moon was begun to be obscured in a clear sky ; she being then 64^" above the 

 horizon. — At Qh. the whole under side of the moon was eclipsed, and about 

 8m. after 9 it was at the height, or rather seemed to decrease. At 9ih. there 

 was still a third part of the moon eclipsed. — About JO it decreased apace, and 

 at 104-h. there was but little to be seen ; at lOh. 45m. it was certainly ended, the 

 moon being then about 22° high. Thus far the observer. 



The duration of this eclipse is here made from 7h. 38m. to about lOh. 45m, 

 which agrees within 8 or 10m. with our tables, that never err sensibly in the 

 continuance of eclipses ; and so much ought to be allowed to an observer not 

 sufficiently instructed to distinguish the penumbra from the true shadow, though 

 a small telescope was used in this observation, as we are since informed. Let 

 us conclude then that the end was at lOh. 40m. at Moscow. This eclipse was 

 observed at Leipsic by Mr. Gotfrid Kirch, and published in his Ephemerides 

 for the year 1689, where the etid is determined at 8h. 54m. P. M. Hence 

 Moscow will be ih. 46m. to the eastward of Leipsic; and the difference of 

 meridians between London and Leipsic being already determined 49m. it will 

 follow that Moscow is 2h. 35m. to the east of London, or 38° 45' of longitude. 



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