258 



SIR DAVID BREWSTER ON THE 



1841, October 12. — Barora. 291. Beautiful morning; the sun rose free of 

 clouds. 



Mean Time. 

 6 h 17 m 

 6 24 



4 54 



5 10 



Va.m. R = 28J-° in zenith, and 26|-° in horizon. 

 > p.m. R=25° in zenith; 27£° near horizon. 



Arago. 

 f 21° 25' 

 (18 20 

 j 18 1 

 (19 57 



1841, October 18 — Barom. 29-5. Wind west ; a very fine day. 



Mean Time. 



3 h m 

 4 42 



R=29.y in zenith, and 26. V 3 near horizon. 



Aratco. 



20° 



1841, October 23. — See " Edinburgh Transactions," vol. xxiii. pp. 215 and 224. 



1841, October 25. — A cold day with a little rain. Wind north, and came 

 round to the east at 4 h . 



Mean Time. 



3 h 57 m R=29° in zenith plane. 



4 13 I R = 29i-° in zenith plane. 



4 17 V Slight clouds. 



4 23 J R=28f° in zenith plane; 27i° 8° above S. horizon. 



1841, October 2G.— Barom. 296. Fine day and cold. 



R=25J° in zenith, sun shining; 27|° sun not shining. 

 Arago's neutral point rose in the N.E. above sea. 

 R = 25J° in zenith ; 28J° in horizon. 

 R = 29° in zenith ; 29 J° in horizon. 



R=28° in zenith ; 27 A" in horizon. 



'eau 



Time 



2 h 



Qm 



2 



29 



2 



29 



4 



22 



4 



35 



4 



47 



4 



53 



4 



24 



4 



37 



4 



50 



4 



55 



Arago. 

 19° 10' 

 20 20 

 20 31 

 20 1 



Arajjo. 



14° 



55' 



22 



17 



20 



40 



20 



35 



22 



39 



Babinet. 



15° 



5' 



15 



55 



16 



55 



15 



36 



1841, October 28.— Barom. 299. Fine day. 



A cloud had just left the neutral point. 

 A little cloud left about the neutral point. 



R = 29-i-° in zenith ; 28 £° 10° altitude N. and S. 

 Maximum polarisation more than 90° from sun. 

 R=26J° in zenith, and at 10° above N. horizon. 



!eai 



l Time 



3 h 



15" 



8 



39 



4 



23 



4 



39 



4 



50 



3 



19 



3 



35 



4 



15 



4 



25 



4 



42 



4 



47 



Arago. 



16° 



48' 



19 



40 



20 



2 



21 



50 



21 



28 



Babinet. 



12° 



15' 



11 



50 



13 



28 



14 



27 



14 



5 



15 



