75 



Professor Bache mentioned that he had received, for the So- 

 ciety, from our fellow member, Mr. Riimker, Director of the 

 Observatory at Hamburg, under date of the 18th of March, 

 1841, a list of observations, made by him at Hamburg, of the 

 last comet of 1840. The observations are as follows: — 





Mean T 



ime at 



Apparent Alt of 



Apparent Declination 



1840. 





Hamb 



urg. 





Comet. 



of Comet. 



Oct. 31 



8 



22 



0.08 



19 







39.467 



60 



55 



28.69 



Nov. 1 



6 



52 



26.82 



19 



5 



43.216 



60 



54 



31.48 



2 



10 



28 



10.86 



19 



12 



4.756 



60 



52 



7.84 



3 



7 



15 



19.82 



19 



17 



2.979 



60 



50 



33.74 



4 



13 



20 



2.14 



19 



24 



28.450 



60 



46 



31.34 



5 



6 



57 



8.31 



19 



28 



56.872 



60 



43 



16.11 



9 



8 



21 



27.13 



19 



56 



59.328 



60 



21 



30.63 



11 



6 



55 



59.20 



20 



8 



40.337 



60 







48.52 



12 



6 



27 



11.41 



20 



15 



41.102 



59 



50 



3.76 



13 



8 



5 



4.80 



20 



23 



26.385 



59 



36 



5.27 



14 



9 



29 



42.97 



20 



31 



14.402 



59 



21 



18.39 



15 



6 



41 



14.84 



20 



37 



50.215 



59 



7 



7.50 



18 



6 



34 



54.83 



21 







40.717 



58 



9 



58.25 



19 



6 



48 



36.13 



21 



8 



29.169 



57 



47 



16.72 



20 



6 



25 



23.65 



21 



16 



6.285 



57 



23 



14.93 



24 



6 



44 



42.53 



21 



47 



13.882 



55 



26 



0.50 



25 



6 



25 



2.60 



21 



54 



47.306 



54 



52 



15.69 





13 



41 



46.60 



21 



57 



7.628 



54 



42 



19.72 



26 



7 



9 



17.20 



22 



2 



38.673 



54 



15 



27.30 



29 



7 



33 



59.12 



22 



25 



6.281 



52 



15 



46.65 



Dec. 2 



9 



11 



4.79 



22 



46 



56.829 



49 



58 



3.17 



3 



7 



7 



2.82 



22 



53 



12.672 



49 



13 



4205 





8 



49 



21.41 



22 



53 



42.254 



49 



10 



52.41 



6 



6 



56 



47.26 



23 



12 



59.638 



46 



43 



49.08 



13 



7 



42 



40 03 



23 



54 



19.495 



40 



19 



3.31 



14 



7 







57.18 



23 



59 



29.358 



39 



24 



18.23 



15 



6 



17 



45.63 







2 



52.297 



38 



29 



703 



16 



8 



50 



43.24 







10 



6.085 



37 



27 



56.16 



18 



7 



34 



23.16 







19 



31.004 



35 



39 



31.85 



19 



8 



47 



55.91 







24 



25 567 



34 



41 



30.99 



21 



8 



2 



41.39 







33 



15.525 



32 



54 



42 36 



23 



7 



58 



57.91 







41 



47.577 



31 



8 



36.33 



25 



7 



42 



27.06 







49 



52.085 



29 



26 



8.12 





10 



34 



11.99 







50 



21.596 



29 



20 



56.22 



26 



8 



8 



10.01 







53 



51.430 



28 



34 



51.10 



27 



9 



31 



19.89 







57 



55.670 



27 



43 



41.96 



Nov. 19, at 7 46 50, mean time, the comet passed over a small star, in AR 

 21 8 51.280, Dec. 57 46 27.32 N. 



Dr. Mitchell presented to the Society a short abstract of a 

 paper, read by Dr. S. Brown, of Edinburgh, before the Royal 

 Society of that city, on the subject of the apparent isomerism 

 of silicon and carbon, and of iron and rhodium. 



The proof sheets of this paper were sent by Mr. Combe, of Edin- 

 burgh, to Dr. Hare, in consequence of whose absence from Philadel- 



