VII.] OPTICAL ILLUSIONS. 263 



selves, would meet with the same fate that befell the Tegcttlioff. 

 In order to avoid this, it became necessary to abandon our 

 attempt to sail from Cape Chelyuskin straight to the New 

 Siberian Islands, and to endeavour to reach as soon as possible 

 the open water at the coast. 



When it cleared on the morning of the 23rd, we therefore 

 began again to steam forward among the fields of drift-ice, but 

 now not with the intention of advancing^ in a griven direction, 

 but only of getting to open water. The ice-fields we now met 

 Avith were very much broken up, which was an indication that 

 we could not be very far from the edge of the pack. But 

 notwithstanding this, all our attempts to find penetrable ice in an 

 easterly, westerly, or southerly direction were unsuccessful. We 

 had thus to search in a northerly direction for the opening by 

 which we had sailed in. This was so much the more unpleasant 

 as the wind had changed to a pretty fresh N.W. breeze, ou 

 which account, with the Vegas weak - steam-power, we couhl 

 make way only slowly. It was not until 6.30 p.m. that we at 

 last came to the sack-formed opening in the ice through which 

 we had sailed in at noon of the previous day. 



One can scarcely, without having experienced it, form any 

 idea of the optical illusions, which are produced by mist, in 

 regions where the size of the objects which are visible through 

 the fog is not known beforehand, and thus does not give the 

 spectator an idea of the distance. Our estimate of distance 

 and size in such cases depend wholly on accident. The obscure 

 contours of the fog-concealed objects themselves, besides, are 

 often by the ignorance of the spectator converted into whimsical 

 fantastic forms. During a boat journey in Hinloopen Strait I 

 once intended to row among drift-ice to an island at a distance 

 of some few kilometres. When the boat started the air was 

 clear, but while we were employed, as best we could, in shoot- 

 ing sea-fowl for dinner, all was wrapt in a thick mist, and 

 that so unexpectedly, that we had not time to take the bearings 

 of the island. This led to a not altogether pleasant row by 

 guess among the pieces of ice that were drifting about in 

 rapid motion in the sound. All exerted themselves as much as 

 possible to get sight of the island, whose beach would afford 

 us a safe resting-place. While thus occupied, a dark border 

 was seen through the mist at the horizon. It was taken for 

 the island which we were bound for, and it was not at first 

 considered remarkable that the dark border rose rapidly, for we 

 thought that the mist was dispersing and in consequence of that 

 more of the land was visible. Soon two white snow-fields, that 

 we had not observed before, were seen on both sides of the land, 

 and immediately after this was changed to a sea-monster, re- 

 sembling a walrus-head, as large as a mountain. This got life 



