10° 



14' 



14 



33 



15 



31 



Babinet. 



19° 



49' 



POLARISATION OF THE ATMOSPHERE. 283 



1844, February 6. — Snow on ground. 



Apparent Time. Arago. 



3 h 13 m 19° r 



Babinet. 



3 19 R=25° maximum polarisation in zenith plane. 17° 58' 



4 2 R = 27 maximum polarisation in zenith, 19J° in hor. 



1844, February 7 —Clouds over zenith; snow. 



Apparent Time. Arago. 



2 h 18 m 18° 13 



1844, February 16.— Barom. 2974; wind west; fine day. 



Apparent Time. 



12 h 14 m R = 26J° maximum polarisation, to 19£° in horizon. 



1 58 R = 26i „ „ 20* „ 



3 1 R=23| „ „ 181 fj 



Arago. 



3 14 Neutral point in horizon. 

 3 20 



3 24 Secondary neutral point in horizon. 



3 33 Sky clouded. 



4 6 Secondary neutral point disappears. 



4 32 



1844, February 21.— See " Edinburgh Transactions," vol. xxiii. p. 220. 

 1844, February 27.— Barom. 2912., rising. Thaw. 



Apparent Time. Arago. 



3 h j 6 m Polarisation of moon 17 J°. 



3 44 14° 10' 



1844, March 7.— Barom. 3003, rising. Fine day. 



Apparent Time. Arago. 



4h 4Rm / White nebulosity in zenith; R=13° maximum 1 «q oa/ 

 \ polarisation. J 



1844, March 27.— Barom. 29-70, rising. 



Apparent Time. Arago. 



5h 40-m Polarisation of moon 22-|-°. 20 40' 



1844, April 11. — Fine day and fine evening; wind west. 



Apparent Time. Arago. 



6 h 23 m R= 27° maximum polarisation, 221° in horizon. 18° 23' 



7 1 18 37 



Babinet. 



6 24 20° 50' 



7 3 19 19 



VOL. XXIV. PART II. 4 H 



