Natural History, fyc. 197 



tallized in stellar pallets, with six rays, along which were disposed 

 other filaments arranged as in feathers, and these again supporting 

 other finer filaments similarly arranged. The angles were sixty 

 degrees, the pallets were extremely thin, perfectly plane, and quite 

 regular in form. 



Previous to the 2d of January of the present year, the quantity 

 of snow of this kind which had fallen was but small, but on the 2d, 

 3d, and 4th of January the quantity was so great, all of the same 

 kind, as to attract general attention ; every body was talking of it, 

 and comparing it to feathers. M. Huber-Burnand ventured to call 

 it Polar SnoWy from its corresponding to the description given of 

 such, and it retained the name.' Whenever this snow fell during the 

 winter, it was found to be of the same kind. Five or six inches f of 

 this snow fell in the three days mentioned. It was extremely light, 

 very dry, and without adhesiveness. Instead of presenting a swan- 

 like whiteness, it had more the silvery appearance of feathers of the 

 colymbus, in consequence of the high polish of its crystalline facets. 

 When this snow was dropped freely into a basin, measured, and 

 then melted, it gave one-forty-fifth its volume of water. 



This snow fell on various occasions during the winter. In the 

 intervals another kind fell, which was called elementary snow. It 

 fell only on foggy days, and was supposed to be formed near the 

 earth. The particles were excessively fine, not regularly crystallized. 

 It fell as a fine powder, but only rarely. Both these kinds of snow 

 fell at temperatures much below that of ordinary snow, namely, at 

 ten or fifteen degrees below the freezing point. 



On the 23d and 24th November, 1829, the temperature being 

 two or three degrees above freezing, it snowed continually for 

 twenty-four or thirty hours, nevertheless it did not accumulate on 

 the ground to a height of more than eight inches, because much of it 

 melted as it fell. The water derived from it amounted to 31 lines, 

 that enormous quantity being collected in the rain-guage. The wind 

 passed during the time from being violent at south-west to the north- 

 west, where it remained. The snow was heavy, and full of water ; 

 it broke the branches of the trees in the neighbourhood, especially 

 the upper ones, upon which it frequently rested to the height of 

 more than a foot. 



The hoar frost of last winter was also abundant and peculiar at 

 Yverdun. It each day affected a different form, being sometimes 

 in parallel fillets, or groupes, sometimes resembling leaves, at others 

 spines, occasionally spines terminated by a flat rosette, with six 

 divisions, &c., the spines being sometimes an inch in length. These 

 arrangements were all alike on the same day. Such effects shew us, 

 that circumstances probably occur with the air of which we are 

 ignorant, although they are sufficiently powerful to have a strong 

 influence in certain phenomena which occur in that elastic fluid *. 



Bib. Univ., 1830, 355. 



