134 FRAGMENTS OF SCIENCE 



of the mountain. Such a one was visible from a point a 

 few hundred feet above the hotel. The Matterhorn also, 

 though for the most part in shade, had a crimson projec- 

 tion, while a deep ruddy red lingered along its western 

 shoulder. Four distinct peaks and buttresses of the Dom, 

 in addition to its dominant head — all covered with pure 

 snow — were reddened by the light of sunset. The shoul- 

 der of the Alphubel was similarly colored, while the great 

 mass of the Fletschorn was all aglow, and so was the 

 snowy spine of the Monte Leone. 



Looking at the Weisshorn through the Nicol, the glow 

 of its protuberance was strong or weak according to the 

 position of the prism. The summit also underwent strik- 

 ing changes. In one position of the prism it exhibited a 

 pale white against a dark background; in the rectangular 

 position it was a dark mauve against a light background. 

 The red of the Matterhorn changed in a similar manner; 

 but the whole mountain also passed through wonderful 

 changes of definition. The air at the time was filled with 

 a silvery haze, in which the Matterhorn almost disap- 

 peared. This could be wholly quenched by the Nicol, 

 and then the mountain sprang forth with astonishing so- 

 lidity and detachment from the surrounding air. The 

 changes of the Dom were still more wonderful. A vast 

 amount of light could be removed from the sky behind 

 it, for it occupied the position of maximum polarization. 

 By a little practice with the Nicol it was easy to render 

 the extinction of the light, or its restoration, almost in- 

 stantaneous. When the sky was quenched, the four minor 

 peaks and buttresses, and the summit of the Dom, to- 

 gether with the shoulder of the Alphubel, glowed as if 

 set suddenly on fire. This was immediately dimmed by 



