The National Geographic Magazine 



Should this rate of retreat continue, 

 the whole of this ice mass, so far as Cap- 

 tain Scott saw it, will have vanished in 

 1,000 years. 



As the motion of the ice mass is also 

 about 15 miles to the north in the same 

 time, icebergs covering collectively an 

 area of 450 miles by 30 have been dis- 

 charged from it in 60 years. 



Captain Scott traveled over it nearly 

 due south to a point 300 miles from its 

 face, and then saw no sign of its end. 



It is bordered on its western side by 

 a mountainous coast line, rising in places 

 to 15,000 feet. He found the ice prac- 

 tically flat and wholly unfissured, ex- 

 cept at the side, where its northerly 

 motion, found to be about 130 feet in the 

 month, caused shearing and vast cre- 

 vasses. All that is known of its eastern 

 edge is that it is bordered, where it 

 meets the sea, by land from 2,000 to 

 3,000 feet high, suspected by Ross and 

 verified by Captain Scott. This may be 

 an island, or more probably the eastern 

 side of the great fiord or bay now filled 

 by the barrier. 



Captain Scott is of opinion that this 

 great ice-sheet is afloat throughout, and 

 I entirely agree with this conclusion. 

 It is unexpected, but everything points 

 to it. From soundings obtained along 

 the face, it undoubtedly has about 600 

 feet of water under it. 



It is difficult to believe that this enor- 

 mous weight of ice, 450 miles by at least 

 360, and perhaps very much more, with 

 no fall to help it along by gravit}^ can 

 have behind it a sufficient force in true 

 land glacier to overcome the stupendous 

 friction and put it in motion if it be rest- 

 ing on the bottom. It is sufficiently 

 astonishing that there is force enough 

 even to overcome the cohesion at the 

 side, which must be very great. 



The flat nature of the bottom of the 

 Ross Sea and the analogies of many geo- 

 graphical details in other parts of the 

 world make it most probable that the 

 water under the whole barrier is deep. 



A point on which I have seen no com- 

 ment is the difference in the appearance 

 of the slopes of Mount Terror. Captain 

 Scott found the bare land showing over 

 large areas, but during the two summers 

 of Ross's visit it was wholly snow-clad. 

 Sir Joseph Hooker, the sole survivor 

 of Ross's expedition, when questioned 

 had no doubt on the subject and pro- 

 duced many sketches in support. 



This may be due to temporary causes, 

 but all the information collected by the 

 expedition points without doubt to 

 steadily diminishing glaciation in recent 

 times. We have, therefore, this inter- 

 esting fact, that both in Arctic and 

 Antarctic regions, as indeed all over the 

 world, ice conditions are simultaneously 

 ameliorating, and theories of alternate 

 northern and southern maximum glaci- 

 ations seem so far disproved. 



But this does not mean that climatic 

 conditions in the Antarctic are now less 

 severe — probably the contrary. It has 

 been pointed out by many that land 

 glaciation may arise from varied primary 

 causes, but one obvious necessity is that 

 the snowfall should exceed melting 

 and evaporation. It need not be heavy, 

 but if it is it may produce glaciation 

 under somewhat unexpected conditions. 

 This would entail a vapor- laden air more 

 or less continuously impinging upon the 

 land at a temperature which will enable 

 it when cooled, either by passing over 

 chilled land or when raised to higher 

 regions by the interposition of moun- 

 tains, to give up its moisture freely. 

 This condition is not fulfilled when the 

 air as it arrives from the sea is already 

 at a very low temperature. 



It was my fortune to spend two long 

 seasons in the Straits of Magellan, and 

 I was daily more impressed by what I 

 saw. 



There you have a mountainous ridge 

 of no great height — very few peaks 

 rising more than 4,000 feet — opposed 

 to the almost continuous westerly winds 

 pouring in from the Pacific at a very 



