The sudden appearance of large masses of deep ice has often been noted in the Arctic Basin. 

 Thus, during the expedition on the Fram, Nansen observed this phenomenon north of the New 

 Siberian Islands, and Sverdrup observed it at 81°30' north, to the northwest of Spitsbergen.* 



Interesting observations of deep ice formation were conducted by Wright and Priestley during 

 the British Antarctic expedition (1910 to 1913). 



These observations were corroborated by Altberg, who noted that during formation of deep 

 ice, the water contains a multitude of ice elements throughout its entire mass, which are hardly 

 noticeable but which, when the observer's eye is in a particular position in relation to the sun's 

 rays, appear as shining points. 



Further, Wright and Priestley also noted that in antarctic conditions, supercooling during the 

 greater part of winter extended to a depth of 8 m. A rope lowered into the water for three days 

 was overgrown with porous ice resembling lace or "fret-work lady's boa" up to 12 cm in diameter. 

 This "boa" gradually narrowed with depth, and at a depth of 8 m disappeared (figure 34). 



Wright and Priestley indicate that deep ice formed independently of whether or not there was 

 any ice on the surface and also independently of the thickness of surface ice. As I was informed by 

 Captain Melkhov during the voyage of the icebreaker Lenin in January, 1942, among solid nilas 

 ice off the Dvina Gulf, he often had the opportunity of observing the following. The icebreaker 

 navigating freely through the nilas at a speed of 5 to 7 knots, sometimes gradually lost headway 





i:m 





.a;..m: 





m 



■-..r 



<.X' 



Figure 34. A rope overgrown by deep ice. 



*In individual cases, deep ice floating up can have a practical effect. Thus, Tanfil'ev notes 

 that in 1879 in the Baltic Sea, several steamers and sailing vessels were suddenly caught by rising 

 ice which rapidly attained considerable thickness, and they had a difficult time extricating 

 themselves. 



101 



