112 SIBERIA. 



saw the rocks and precipices of tlir promontory roilectod on a smooth 

 surface of open water; but, in a few moments, what liad appeared open 

 water seemed changed to a smooth surface of ice, which presently be- 

 came covered with numerous inequalities varying their form every histant. 

 At last, as the position of the sun was a little altered, the whole disap- 

 peared, and we saw clearly an almost impassable range of enormous ham- 

 mocks extending in every direction." The strong refraction of the rays 

 of light, constantly varying with the relative change of position between 

 the sun and the ice, renders these illusions very frequent; and often they 

 mislead the traveler. Among the ice-bergs of the Arctic Ocean they as- 

 sume all the fantastic forms that fancy can create ; resembling well 

 built and populous cities, with numerous churciies and steeples, and again 

 the solitary castle, frowning in lonely grandeur and proud defiance upon 

 the plains beneath. 



A more remarkable case of illusion was seen by M. Kosmin. a com- 

 panion of Mr. Wrangell, in his polar expedition. The sun had been shi- 

 ning constantly during seventy-two hours in a clear aiid cloudless sky. 

 This was the last day that they saw it in its full magnificence, height- 

 ened by the refraction which the great evaporation from the sea produ- 

 ced. The size of its disk and its altitude appeared to vary constantly. 

 One moment it seemed to contract, then to assume an eliptical form and 

 to sink into the ocean. Then it would suddenly rise again in full size 

 and majesty, and float above the horizon in a flood of red or yellow 

 light. This magnificent spectacle continued throughout the day, nor 

 could they refrain from gazing on it notwithstanding the pain which the 

 brilliant liglit caused to their eyes. 



The characteristics of the Aurora Borealis, so common in high lati- 

 tudes, are well known. But certain facts, ascertained by personal obser- 

 vation in this expedition, should not be overlooked. On one occasion 

 there appeared in the N. E. horizon an insulated grey cloud, during the 

 da)', from which white beams streamed to the zenith and across it to the 

 opposite horizon resembling the streams of the Aurora. They continued 

 about one half an hour. Sometimes the Aurora appeared to be nearer to 

 them than the ordinary height of the clouds, but no effect was visible on 

 the compass-needle. When shooting stars fell near the lower portion of 

 an auroral arch fresh kindled streams immediately shot up from the spot 

 where the stars fell. The Aurora is usually near the surface of the earth. 

 This is shown by the visible influence of the lower current of the atmos- 

 phere upon its beams. The eflect of the wind has been as clearly seen 

 on the streamers as on the clouds, and it is almost always the wind that 

 is blowing at the snrface of the earth. It has been supposed that the 



