GREEN SUNS AND RED SUNSETS. 601 



tween the arch and the western horizon " a sky of a bright silver- white 

 color, which was so brilliant that it gave us quite a second daylight " ; 

 at another, of the sky nearer the zenith appearing "of a sea-green 

 tint." The sea-green tint in the east was observed at Rome ; and at 

 Berlin, according to Herr Robert von Helmholtz, there was " a green- 

 ish sunset at 3.50, an unusually bright-red sky with flashes of light 

 starting from southwest. An interesting physiological phenomenon 

 which recalls ' Contrast-Farben ' was there beautifully illustrated by 

 some clouds, no longer reached by direct sunlight ; they looked in- 

 tensely green on the red sky." The whole phenomenon was exhibited, 

 according to Mr. J. Addington Symonds, with remarkable intensity at 

 Davos-Platz in the High Alps ; and on one occasion " the whole north- 

 eastern region of the heavens was at the same time of the most vivid 

 golden-green the peculiar green of chrysoprase and some highly- 

 tinted beryls. Each tone of light, rose and green, was reflected on 

 the long, broad basin of valley snow, the blending of both colors being 

 of a strange, bewildering brilliancy." The sun, at this place, appeared 

 through the day " surrounded by a luminous, slightly opalescent haze 

 not at all resembling halo or iridescence of vapor." 



The red glow and the green sun are most likely due to a common 

 cause. The same medium which will give by transmitted light a 

 green color to objects viewed through it, will, by the universal law of 

 the absorption and reflection of light, reflect the red rays. The close 

 connection of the two phenomena may be regarded as real. 



The spectacle must be due to some peculiar condition of our atmos- 

 phere, for, if it was produced by any cause outside of the atmosphere, 

 it would have been visible in some form through the night, whereas 

 its duration corresponded tolerably closely with that of ordinary twi- 

 light ; the cause must have been co-extensive with the atmosphere, for 

 the glow lasted as long as the twilight, if not longer. The manifes- 

 tation was not auroral or electrical, for no auroras have been seen 

 which could reasonably be associated with it, and no electrical dis- 

 turbances have been mentioned in connection with it, except at Ma- 

 dras. Professor Michie Smith, of Madras, and Professor C. Piazzi 

 Smyth, believe that it is the result of peculiar conditions of vapor in 

 the air ; but, while this might easily account for colors lasting a few 

 days, it is difficult to suppose a peculiar accumulation and distribution 

 of ordinary vapors enduring for so long a period. Nevertheless, Mr. 

 Lockyer has seen the sun green through the steam of a steamboat ; 

 it has been seen green through the mist of the Simplon ; and Mr. 

 Henry Bedford, describing the summer sunset and sunrise just within 

 the Arctic Circle in July, 1878, in an English magazine of that year, 

 said : " The color brightens, and some small streaks of clouds grow 

 brighter and brighter, until the sun the green sun appears. A 

 distant low range of rocks comes between us and its point of rising, 

 and, as we glide on, an opening between them shows us the sun, a 



