SCIENTIFIC ADVANTAGES OF AN ANTARCTIC' EXPEDITION. 415 

 ANTARCTIC ICE. 



From many points of view it would be important to learn something 

 about the condition and distribution of Antarctic sea ice during the 

 winter months, and especially about the position and movements of 

 the huge table shaped icebergs at this and other seasons of the year. 

 These flat- topped icebergs, with a thickness of ],200 or 1,500 feet, with 

 their stratification and their perpendicular cliffs, which rise 150 or 200 

 feet above and sink 1,100 or 1,400 feet below the level of the sea, form 

 the most striking peculiarity of the Antarctic Ocean. Their form and 

 structure seem clearly to indicate that they were formed on an extended 

 land surface, and have been pushed out over low-lying coasts into 

 the sea. 



Ross sailed for 300 miles along the face of a great ice barrier from 

 150 to 200 feet in height, off' which he obtained depths of 1,800 and 2,400 

 feet. This was evidently the sea front of a great creeping glacier or 

 ice cap just then in the condition to give birth to the table-shaped 

 icebergs, miles in length, which have been described by every Antarc- 

 tic voyager. 



All Antarctic land is not, however, surrounded by such inaccessible 

 cliffs of ice, for along the seaward faces of the great mountain ranges 

 of Victoria Laud the ice and snow which descend to the sea apparently 

 form cliffs not higher than 10 to 20 feet, and in 1895 Kristensen and 

 Borchgrevink landed on a pebbly beach occupied by a penguin rookery 

 at Cape Adare without encountering any land ice descending to the 

 sea. Where a penguin rookery is situated we may be quite sure that 

 there is occasionallj^ open water for a considerable portion of the year, 

 and that consequently landing might be effected without much difficulty 

 or delay; and further, that a party, once landed, might with safety 

 winter at such a spot, where the jienguins would furnish an abundant 

 supply of food and fuel. A properly equipped party of observers 

 situated at a point like this on the Antarctic Continent for one or two 

 winters might carry out a most valuable series of scientific observations, 

 make successful excursions toward the interior, and bring back valuable 

 information as to the probable thickness of the ice-cap, its temperature 

 at different levels, its rate of accumulation, and its motions, concerning 

 all which points there is much difference of opinion among scientific 

 men. 



ANTARCTIC LAND. 



Is there an Antarctic Continent? It has already been stated that 

 the form and structure of the Antarctic icebergs indicate that they were 

 built up on and had flowed over an extended land surface. As these 

 bergs are floated to the north and broken up in warmer latitudes they 

 distribute over the floor of the ocean a large quantity of glaciated rock 

 fragments and land detritus. These materials were dredged up by the 

 Challenger in considerable quantity, and they show that the rocks over 



