312 Latitude and Longitude of Yale College Observatory, 



EDINBURGH AND NEW HAVEN. 



The longitude of Cambridge is taken at — 23.54s. ; and that 

 of Edinburgh at + 12m, 43.6s. ; and the mean of the preceding 

 ten observations gives the longitude of New Haven from Green- 

 wich 4h. 51m. 37.7s. Mean difference, rb 8.4s. 



In addition to these observations, on the 9th of August, 1835, 

 two occultations were observed, viz. of t ' and t^ Aquarii. The 

 immersion of the former occurred at 19h. 13m. 51.5s. sidereal 

 time ; that of the latter, at 20h. 57m. 12.5s. I failed to note the 

 emersions with sufficient accuracy to be of any use. To derive 

 any valuable result from these observations, we need to know the 

 true places of the moon and the above stars. From observations 

 made at Greenwich, and published in Vol. ix. of the Memoirs of 

 the Royal Astronomical Society, it appears that 1.11s. should be 

 subtracted from the moon's right ascension, as given in the Nau- 

 tical Almanac for August 9th. How great may be the error of 

 the moon's declination as given by the tables, I have no satisfac- 

 tory means of determining. From the observations of Prof. Hen- 

 derson, however, (Mem. Ast. Soc. Vol. ix. p. 273.) it may be 

 presumed that this error is well nigh insensible. The places of 

 both of the stars are taken as they are given in the Nautical Al- 

 manac, and from observations at Greenwich, it appears that the 

 right ascension of the latter at least was very correctly computed. 

 The longitude resulting from the observation of t' Aquarii, is 4h. 

 52m. 17s., and from t^ Aquarii, 4h. 51m. 58s. The first of these 

 differs 39s. from the mean of my former determinations, which 

 would seem to indicate either that the star's place was somewhat 

 different from what it was assumed, or that the observation was a 

 poor one. Finally, the longitude deduced from the eclipse of 

 1811, according to the computation of Dr. Bowditch, is 4h. 51m. 

 51s. Bringing then together the results of all the different ob- 

 servations, we have : 



June 7, 1835, Greenwich observation, 4h. 51m. 33s. W. long. 

 " Cambridge " 25 " 



