163 



A further comparison was furnished from the observations of the 

 solar eclipse of Sept. 18th, 1838, as reduced by Prof. Kendall, and 

 from those of several occultations reduced by Mr. Walker. 



Comparisons with the High School Observatory. Assumed longi- 

 tude — 5h. Om. 42s. Resulting longitude of Nassau Hall, 



h. m. s. 



1838, Sept. 18th. Solar Eclipse four phases,— 4 58 37.64 weight 2.0 

 Nov. 21, Irn. a Sagittarii, 34.62 1.0 



h. in. s. 



Dec. 27, Im. >; Pleiadum, — 4 58 39.42 ) 



" " f " 36.35 V 36.80 1.7 



" « h " 34.62 ) 



1839, April 19, " c Geminorum, 39.84 1.0 



No. 3, Mean according to weights, — 4 58 37.25 5.7 

 Comparisons with the State House, Boston. Assumed longitude 

 — 4h. 44m. 16.6s. 



h. in- s. 



1838, Dec. 24, Im. t Piscium, -— 4 58 39.56 weight 1.0 



27, Im. f Pleiadum, 36.35 1.0 



h. in. s. 



1839, April 19, Im. c Geminorum, — 4 58 39.31 ) 0097 -1 * 



Do. at Dorchester Obs'y. 39.22 $ dy,<57 1#4 



No. 4. Mean according to weights — 4 58 38.49 3.4 



The Immersion of f Pleiadum was also observed by Prof. Boguslawski 

 at the Breslaw Observatory, longitude -f- Ih. 8m. 10.4s., whence 

 Nassau Hall — 4h. 58m. 41.15s. No. 5, weight 1. This result is 

 somewhat uncertain, from the variation of the co-efficient of the un- 

 known error £ of the moon's tabular place on a secondary to its orbit ; 

 since we have for the longitude, d = — 4h. 58m. 41.15s. — 2.353 

 X f — 0.406 x k, according to Bessel's Notation. 

 The mean results taken with their weights gave, 



li- m. s. 



No. 1 — 4 58 38.51 weight 6.0 



2 38.07 3.0 



3 37.25 5.7 



4 38.49 3.4 



5 41.15 1.0 



Mean according to weights — 4 58 38.20 19.1 



Thus it appears that the observations of the 25th November, 1835, 

 lead to the same conclusion as that which was subsequently in 1839, 

 obtained by the European astronomers. 



