318 THE VOYAGE OF THE VEGA. [chap, 



temperature of the air was above the freezing-point. On this 

 occasion, when the temperature of the uppermost stratum ot 

 water was also above the freezing-point, the formation of ice 

 was clearly a sort of hoar-frost phenomenon, caused by radiation 

 of heat, perhaps both upwards towards the atmosphere and 

 downwards towards the bottom layer of water, cooled below 

 the freezing-point. 



The whole day we continued our voyage eastwards with 

 glorious weather over a smooth ice-free sea, and in the same 

 way on the 1st September, with a gentle southerly wind, the 

 temperature of the air at noon in the shade being + 5°"6. On 

 the night before the 2nd September the wind became northerly 

 and the temperature of the air sank to — 1°. Little land was 

 seen, though we were still not very far from the coast. Near to 

 it there was a broad ice-free, or nearly ice -free, channel, but 

 farther out to sea ice conmienced. The following nig^ht snow 

 fell, so that the whole of the deck and the Bear Islands, which 

 we reached on the 3rd September, were sprinkled with it. 



Hitherto, during the whole time Ave sailed along the coast, we 

 had scarcely met with any fields of drift-ice but such as were 

 formed of rotten, even, thin and scattered pieces of ice, in many 

 places almost converted into ice-sludge, without an "ice-foot" 

 and often dirty on the surface. No iceberg had been seen, nor 

 any large glacier ice-blocks, such as on the coasts of Spitzbergen 

 replace the Greenland icebergs. But east of Svjatoinos the ice 

 began to increase in size and assume the same appearance as 

 the ice north of Spitzbergen. It was here, besides, less dirty, and 

 rested on a hard ice-foot projecting deep under water and 

 treacherous for the navigator. 



The ice of the Polar Sea may be divided into the following 

 varieties : — 



1. Icebergs. The true icebergs have a height above the 

 surface of the water rising to 100 metres. They often ground 

 in a depth of 200 to 300 metres, and have thus sometimes 

 a cross section of up to 400, perhaps 500 metres. Their area 

 may amount to several square kilometres. Such enormous 

 blocks of ice are projected into the North Polar Sea only from 

 the glaciers of Greenland, and according to Payer's statement, 

 from those of Franz-Josef Land also ; but not, as some authors 

 (Geikie, Brown, and others) appear to assume and have shown 

 by incorrect ideal drawings, from glaciers which project into the 

 sea and there terminate with a perpendicular evenly-cut border, 

 but from very uneven glaciers which always enter the sea in the 

 bottoms of deep fjords, and are split up into icebergs long befoi'e 

 they reach it. It is desirable that those who write on the 

 origin of icebergs, should take into consideration the fact that 

 icebergs are oidy formed at places where a violent motion takes 



