346 Sir David Brewster on the Polarization 



currents, may be effected in this way. If this view be accepted, 

 muscular disintegration, so far from beiug the cause of muscular 

 work, must rather be regarded as an effect contingent upon it. 



Ranke's beautiful experiments upon the effect of the products 

 of muscle-metamorphosis in checking muscular contraction by 

 increasing the conductivity of the tissue, are in perfect accord- 

 ance with Mayer's theory. 



XLVIII. Additional Observations on the Polarization of the Atmo- 

 sphere, made at St. Andrews in 1841, 1842, 1843, 1844, and 

 1845. By Sir David Brewster, K.H., D.C.L., F.R.S., %b. 



[Continued from p. 304.] 



1842, January 6. — Fine day. 



Apparent time. Arago. 



a m o 



2 34 . . . . . . . . 19 6 



Babinet. 



2 38 .. .. .. .. 16 18 



R = 2i° in zenith plane; 28^° at 30° above E. horizon. 



1842, January 7. — Very fine day, with haze. 



9 18 a.m. . 

 12 noon . 



11 52 a.m. . 



12 4 p.m. . 



3 25 



4 17 



15 51 

 13 53 



Argo. 



20 34 



22 



12 9 „ R=22r in zenith .. .. 22 3/ 



20 40 

 19 49 



At 9 b 18 m It = 24°, a maximum, in horizon. The neutral 

 line was convex to the sun. Sky clear, without clouds. 



1842, January 16. — Ground everywhere covered with snow. 



Babinet. 



4 12 p.m. .. .. .. .. 19 25 



1842, January 17.— Fine clear day; therm. 36°. 



8 37 a.m. R=24i° at 35° alt., 20i° in horizon. 16 55 

 3 47 p.m. R=25° in zenith; 24f° in horizon. 



Neutral line concave towards the 



sun. 



1842, January 21. — Barom. 29'77 in. ; dry, frosty day. 



Arago. 



3 34 I R=27|° in zenith plane, and 24^° i ,q 4Q 



| near horizon j 



Babinet. 



3 31 ... .. .. .. 19 3 



