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MR. RUMKER'S OBSERVATIONS 



«j(l ramatta and Sydney, the diflfei-ence of longitude between both places was 



found51".93. 



My calculation of the above solar eclipse observed by Sir Thomas Brisbane 

 in Sydney, and myself at Paramatta, gives 



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From Beginning, 

 h m 



rrn . ^. , ("Sydney 21 26 51.8 



The conjunction at I p^^^J^^^^ . . 21 25 55.32 



End. 

 h m s 



21 26 34.38 

 21 25 42.40 



Hence DifF. of Long 56.48 51.98 



But I believe we must reject the results from the beginning, and hold our- 

 selves to that from the end 5P.98. 



Professor Wurm has computed my observations at Paramatta of the transit 

 of Mercury over the sun's disk 5th November 1822, as follows : 



Conjunction. 



Inner Contact, 

 h m s 



Immersion 23 7 19.78 



Emersion 1 49 8.43 



Outer Contact. 



Immersion 23 4 39.20 



Emersion 1 52 6.92 



5 35.48 + 27.087 X. 

 8 13.66 — 13.297^7. 



6 32.82 + 25.944^7. 

 8 10.02 — 12.953 J?. 



Professor Wurm has also calculated the observations made of this phaeno- 

 menon by Sir Thomas Brisbane at Sydney, and has had the goodness to com- 

 municate his calculation to me, viz. 



"Immersion . 

 Emersion . . 

 Sydney mean time< 



j Immersion . . 23 5 23.22 7 

 LEmersion . , t 1 53 0.34 9 



Professor Wurm adds : 



" Thence follow immediately the differences of longitude between Sydney 



and Paramatta : * 



Inner Contact, 

 h m s 



23 8 6.28 

 1 50 1.83 



Outer Contact. 



23 5 23.22 

 1 53 0.34 



Conjunction. 



62.20 + 27.068 X. 

 3.42 — 13.286 X. 



22.08 + 25.923 J-. 

 0.68 — 12.943 x. 



Per Immersion. 



Per Emersion. 



+ 49.76 + 0.011 a-. 

 + 50.66 4- 0.010 X. 



By inner contact ....-,+ 49.30 — 0.024 x. 

 By outer contact ..... -j- 49.26 — 0.021 x. 



" The mean of all four phases gives -\- 49*.75, or that of the inner contact 



only (as the observation most to be depended on) + 49'.53, which result 



cannot be materially altered by the small coefficient of x. I found, however, 



« =s -J- 3».917. 



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