92 DISCOVERY REPORTS 



found on this side, and further soundings here may well show that these are part of a continuous ridge 

 across the top of this part of the bank, although, as noted above, the ' Schwabenland's' observations 

 suggest that this area of less than 500 m. (273 fm.) in depth may be more of a plateau than a ridge. 

 We have not obtained sufficient information to determine the extent of the shallow water on the 

 eastern half of the bank, though it seems probable that it extends some miles farther to the east. The 

 least depth found here was 390 m. (213 fm.). 



Two attempts were made to dredge on the Discovery Bank and the second, in November 1938, was 

 successful. This was at St. 2493, in 42° 03-9' S, 00° 03-5' E, where three large rocks, a large number 

 of smaller rock fragments and a mass of pebbles were obtained from a depth of 472 m. (258 fm.). 

 Many of these pebbles were round and waterworn. All living organisms were smashed by the weight 

 of rocks and pebbles but it was evident that a large species of sea-urchin and two or three species of 

 Crinoid were common. 



THE ROSS SEA 

 (PI. XXV) 



Soundings taken by Rear-Admiral Byrd's ship the ' Bear of Oakland ' between the years 1933 and 

 1935 and by the 'Discovery II ' in 1936 have provided much valuable information on the topography 

 of the bottom of the Ross Sea. Prior to the work of these two ships our knowledge of the outlines of 

 the sea bed here was scanty, and the few bathymetric charts available were based on a small number of 

 scattered soundings, most of which were near the land on the western side, or were adjacent to the 

 Ross Ice Barrier. 



The most recent bathymetric chart of the Ross Sea, on a scale comparable to that of our present 

 chart, is that of the American Geographical Society (1928). This map, of which sheets 3 and 4. cover 

 the Ross Sea, includes a depth contour at 500 m. (273 fm.). Maps of a more recent date which include 

 this area have been published, but they are on a much smaller scale, and the lack of a 500 m. contour 

 in the Australian map of Antarctica (see p. 67) for instance, prevents the inclusion of most of the 

 interesting features of the bottom topography of the Ross Sea. The U.S. Chart of Antarctica (see p. 67) 

 also shows no depth contour above 500 fm. (914 m.), but more use appears to have been made of 

 soundings taken by the ' Bear of Oakland '} 



Most of the soundings taken by the ' Bear of Oakland ' were obtained during direct passages to and 

 from the Bay of Whales and while cruising to the north and east of Cape Colbeck. The list of soundings 

 also includes observations made during a cruise to meet the 'Discovery 11' (in approximately 72"" S, 

 171° W). Further soundings available from the same source were taken on the return of the ' Bear of 

 Oakland' from New Zealand in 1935, when a cruise was made towards McMurdo Sound and thence 

 south to Ross Island. From here the line of soundings ran across to the Bay of Whales, following 

 closely the face of the Ross Barrier. 



The soundings obtained by the 'Discovery II' in 1936 are shown in black in PI. XXV and their 

 location was determined largely by the necessity for quick passages, to and from the Bay of Whales, 

 through the belt of pack-ice to the north of the Ross Sea. Some scientific work, however, was possible 

 near the Bay of Whales and in the neighbourhood of Ross Island, and the soundings thus obtained 

 have been of material aid in linking up our work with that of the ' Bear of Oakland '. 



Our soundings are mostly in excellent agreement with those of the ' Bear of Oakland ' where the 

 two ships covered the same ground ; but they also provide new information which, when added to the 



1 It is possible that the compilers of the Australian map did not have access to the full list of echo soundings taken by the 

 ' Bear of Oakland '. These were published in manuscript form only, by the Woods Hole Oceanographic Institution, in October 

 1935. Reference in literature to this list does not appear to have been made other than by Roos (1937). 



