Polarization of Sky Light, 97 



On the evening of the 17th, finding the polarization more 

 within the power of the instrument than it had been at St. 

 Moritz, 1 followed it up to sunset. 



April 17. 

 G. r. s. 

 4.25 P.M. 521° -224 -58 At highest point. 

 5.20 54 '212 '54 A few clouds near horizon. 



About 5.30 the sun disappeared behind the hill at an altitude 



[of, perhaps, 10°. 

 5.33 561 -195 .48 



Soon after this a bank of clouds came up over the place 

 when the sun had disappeared, and by 5.45 the shadow had 

 crept up to a height of 1200 feet on the hiUs close by. 



G. 



r. 



s. 



5.45 P.M. 56f 



•193 



•48 



6.5 57 



•192 



•47 



6.20 591 



•178 



•44 



By 6.20 a good many small clouds had come over the sky. 

 At 6.25 both the clouds and all the mountains in sight were 

 in shade, and the polarization was too strong to be read. I 

 estimated it at G = 64°, r="15, s = '35. 



I have taken a few observations at Davos during the summer, 

 altitude 5100 feet above sea-level. The situation is not unlike 

 that of St. Moritz. 



May 12, 12.30 P.M. 38° '372 l-i8 At highest point. 



Sky practically cloudless. At this date the snow was still 

 lying on the south side of the valley down to the level ground, 

 but the north side was tolerably clear. 



G. r. s. 



June 2, 12.30 p.m. 47° -334 I'OO At highest point. 



Sky practically cloudless. The snow came down to within 

 2000 feet of the valley-floor on the south side. 



Aug. 9, 1.0 P.M. 58° -185 ^45 Sky cloudless. 

 Scarcely any snow to be seen on the mountains. 



G. r. s. 



Sept. 23, 10.0 A.M. 61° -167 ^40 Sky almost cloudless. 



Probably even less snow on the mountains. 

 FhU. Mag. S. 5. Vol. 27. No. 165. Feb. 1889. H 



