302 Sir David Brewster on the Polarization 



1841, October 18. — Barom. 29*5 in. Wind west ; a very fine 



Mean time. 



h m Arago. 



3 R=29£° in zenith, and 26^° near horizon. 



4 42 .. .. ... .. 20 5 



1841, October 23. — See Philosophical Magazine vol. xxx. pp. 

 122 & 162. 



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

 north, and came round to the east at 4 h . 



3 57 R = 2.9i° in zenith plane .. 19 10 



4 13 ) R=29i° in zenith plane . . ( 20 20 

 4 17} Slight clouds .. .. ^20 31 

 4 23 ) R=28f° in zenith plane; 27i° at 8° ( 20 j 



ahove S. horizon . . 



1841, October 26.— Barom. 29'6 in. Fine day and cold. 



2 R = 25§° in zenith, sun shining; 27\° 



sun not shining. 

 2 29 Arago's neutral point rose in the N.E. 



above sea. 



2 29 R=25i° in zenith; 28^° in horizon. 14 55 

 4 22 R=29° in zenith; 29^° in horizon. 22 17 

 4 35 . . . . . . . . 20 40 



4 47 R=28° in zenith; 271° in horizon. 20 35 

 4 53 .. 22 39 



Babinet. 



4 24 .. .. .. .. 15 5 



4 37 .. .. .. ... 15 55 



4 50 .. .. .. .. 16 55 



4 55 .. .. .. .. 15 36 



1841, October 28.— Barom. 29'9 in. Fine day. 



Arago. 



3 15 A cloud had just left the neutral point. 16 48 

 8 39 .. .. .. .. 19 40 



4 23 A little cloud left about the neutral point 20 2 



4 39 21 50 



1 50 .. .. .. .. 21 28 



Babinet. 



3 19 R=29£° in zenith ;28^° 10° alt. N. and S. 12 15 



3 35 .. .. .. .. 11 50 



4 15 Max. polarization more than 90° from sun. 13 28 

 4 25 . . . . . . . . 14 27 



4 42 R=26i° in zenith and at 10° above N.hor. 14 5 

 4 47 .. .. .. .. 15 4 



1841, November 2. — See Philosophical Magazine, vol. xxx. 

 pp. 122 & 162. 



1841, November 4. do. do. do. 



