POLARISATION OF THE ATMOSPHERE. 277 



1843, March 12. — Barom. 2934, after rain. 



Apparent Time. Arago. 



4.h om / R = 25|° maximum polarisation. Polarisation I .„ c , „ 

 \ of moon 7°. J 



1843, March 25.— See " Edinburgh Transactions," vol. xxiii pp. 220, 226. 

 1843, March 28— Barom. 29-84. Wind east ; dry. 



Apparent Time. Arago. 



6 h 2 m 16° 45' 



1843, March 29.— Barom. 29-88. Fine day, cold ; wind east; dry. 



Apparent Time. Arago. 



3 h 51™ R=28|°, 25J° in S. and 26|° in W. horizon. 



5 58 18° 35' 



6 26 19 33 



Babinet. 

 6 1 R=29|° maximum polarisation in zenith, 28° in hor. 18° 22' 



6 24 R=29|° „ „ „ 18 27 



1843, April 7. 



Apparent Time. Arago. 



6 h 54 m 19° 0' 



Babinet. 

 6 48 16° 29' 



1843, April 10.— Barom. 2974. Very cold wind, north-west. 



Apparent Time. Arago. 



6 h 23« 20° 42' 



Babinet. 

 6 25 22° 23' 



1843, April 11.— Barom. 2980. Very cold. 



Apparent Time. Arago. 



6 h 43 m R = 28J° maximum polarisation. Sky whitish blue. 17° 30' 



6 48 17 45 



1843, April 12.— Barom. 2977. 



Apparent Time. Babinet. 



4 h 35 m 41° 35'! 



The sky was covered with a thick haze ; the sun barely seen through it, and 

 showers of hail falling occasionally. The bands a maximum above the sun, 

 but disappeared 9° above horizon. A neutral point was seen at 25° alt. opposite 

 the sun, but the bands below it seemed 4- ! though extremely faint. 



1843, April 17.— See " Edinburgh Transactions," vol. xxiii. p. 226. 



Apparent Time. Arago. 



6 h 30 m R=25 *° maximum polarisation in zenith, 201° in hor. 22° 32' 



7 4 R=29 „ „ " „ 20 44 

 7 30 R = 29| „ „ „ 20 10 



