part 2] MODE OF TBANSPOETATION BY ICE. 53 



The first discoveries are described by Mr. Ferrar in the following 



words : — 



' Among the moraines on the west side of McMurdo Sound (Gi), as well as 

 on one of the Dellbridge Islands (Ai). and among- the moraines on the west 

 side of Discovery Gulf (G), great deposits of sodium sulphate in well-formed 

 crystals have been found. Among the isolated moraines in the bay between 

 Black and White Islands (C & Ci) large bosses or mounds of the same white 

 salt have been seen ; and at one spot near White Island a mass of perfect 

 crystals was found on the surface of pure ice. In the White-Black Island bay 

 Balanus shells and sponge- spicules occurred upon the ice in association with 

 tli is salt. The occurrence of this salt, mingled with shells and ice-scratched 

 stones, is a freak of Nature which is difficult to explain.' ' 



In a further reference to the matter lie describes the mounds 

 above mentioned as five or six in number, 2 feet high and up 

 to 5 feet across. He also mentions a bed of the salt in the 

 moraines on the west side of the Sound as being about 18 inches 

 thick, and traceable horizontally for about 30 feet. 2 



He records the discovery of a Pecten shell, 



' in gravel 10 miles up the Ferrar Glacier and 20 feet above the sea. The 

 gravel had formed a glacier-table and the ice around was .all glacier-ice, 

 but is not above the reach of some exceptional tidal wave ' (H).' ;i 



On the next expedition to the Ross Sea the geologists, Prof. T. 

 W. Edgeworth David and Mr. 11. E. Priestley, found raised 

 marine material in five distinct localities, one of which is outside 

 the region of McMurdo Sound, and is especially important on that 

 account. The latter was discovered by Prof. David on the floating 

 ice north of the Drvgalski Glacier-tongue in lat. 75° S. An 

 accurate description of the occurrence is published, together with 

 diagrams which prove it to be quite clearly the exact counterpart 

 of those described from McMurdo Sound. 



In brief, it consisted of a bluish-grey clay covering a conical 

 mound of ice to a depth of a few inches, itself covered in parts 

 with large erratic boulders. With the clay and attached to some 

 of the boulders were the marine organisms. They comprised ser- 

 pulae, large foraminifera, polyzoa, echinoid spines, and sponge- 

 spicules. To one of the big granite erratics was attached a 

 very large compound sponge, in a state of perfect preservation. 

 The underlying iee was stated to be ' slightly saline superficially, 

 but not as salt as typical sea-ice.' 4 



The organisms were identified by Mr. Hedley & Mr. Chapman 

 as belonging normally to depths up to 100 fathoms, and in general 

 were found to be similar to the collections made by trawling 

 at that depth at the present day. The significance of the exact 



1 ' The Voyage of the Discovery ' 1901-04, vol. ii, app. i. 



2 National Antarctic Expedition, 1901-04, Natural History, vol. i (Geology) 

 1907, p. 91. 



3 Ibid. p. 79. 



4 British Antarctic Expedition, 1907-9, vol. i (Geologv) cliapt. xvii. 



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