ANTARCTIC ADVENTURE AND RESEARCH 



perature is well below 28° F. (the freezing point of 

 sea water), the water congeals as soon as its motion 

 is arrested, and this occurs when it has been dashed 

 on to the ice foot. The natural consequence is that on 

 all exposed coasts the ice foot becomes much thicker, 

 often much broader and in general much less level and 

 less like an esplanade. 



Since the ice walls at the front of a glacier are al- 

 most universally vertical, when they happen to reach 

 the sea, there is never an ice foot along a glacier coast. 



Moreover, there is a very considerable elasticity in a 

 glacier, even though it be five hundred feet thick. 

 Hence there is usually no tide crack at the distal end 

 of a floating glacier tongue. As the proximal end is 

 approached, where it merges into the fixed ice over the 

 land, the tide crack begins to appear and close to the 

 root of the tongue it is as wide and striking a feature 

 as along a fixed piedmont glacier or a rock coast. 



Width of the Pack Ice 



This varies very greatly from year to year, and this 

 is perhaps the chief difficulty in determining programs 

 of an expedition's work. Thus the ''Nimrod" in Janu- 

 ary, 1908, met with no pack at the mouth of the Ross 

 Sea, though enormous fleets of bergs were passed in 

 the latitude of the pack. In December or January the 

 pack ice is here found between latitude 66° S. and 

 latitude 72° S., though these limits have been exceeded 

 at times. When the "Terra Nova" entered the pack on 

 the ninth of December, 1910, we hoped to be through 

 it in a few days. But we were still within it on 



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