DEPTHS AND DEPOSITS OF THE WEDDELL SEA. 
787 
country is now completely ice-covered, except for some nunataks in the extreme 
south in 78° S. lat., the solid rock below is nevertheless sculptured into hills and 
valleys. This is indicated not only by the irregularity of the soundings, but also by 
the uneven, mountainous character of the snow-covered land itself. 
( 4 ) West of the deep channel down the centre of the sea there is a somewhat 
sharper rise than to the east ; and there are also more uniform conditions on the 
shelf itself. The Endurance drifted on to the shelf in the last week of March 1915. 
Up till then the total number of casts which had found bottom was thirty-five ; 
besides these, there were some doubtful and some incomplete soundings, not without 
importance. Once on the shelf, soundings could be made without the sinking weight 
having to be sacrificed each time ; a daily cast therefore became the rule. From 
March 31 till July 31 (both inclusive) 103 soundings were made. All of these 
were in depths under 275 fathoms. 
In a way this series of soundings on the continental shelf was unique, and it 
would have been a matter of surprise if some important result had not been the 
outcome of it all. The majority of the soundings clustered round 180-190 or 
250-260 fathoms. Over a large area the depth was about the same, day after day, 
and then it would suddenly change to another level. The back and forward drift 
of the ship now had its uses, for the numerous soundings are so distributed as to 
N.W. s 5 S - E - 
The stepped terraces on 'the continental shelf. Vertical scale much exaggerated. The most north-westerly terrace 
is eighty miles broad, and at least seventy in length (i.e. from south-west to north-east), and so on. 
prove the existence of a series of stepped terraces with boundaries running N.E.- 
S.W. ; these run at right angles, apparently, to the presumed coast line farther to 
the south-west, but are parallel to the known coast line of the Leopold and Caird 
Coasts of Coats Land. The stepped terraces extend from 76° 18' S., 38° 23' W., to 
72° 37 r S., 47° 47' W., a distance of about 270 sea miles. The line so measured (i.e. 
across the terraces) represents very nearly the mean course of the ship’s drift from 
S.E. to N.W. ; at the same time, however, she was drifting sometimes more to the 
north-east, at other times more to the south-west ; and in neither direction did the 
water show the least sign of shoaling. The extent of this shallow area therefore 
came to be known as at least forty miles across in the south-east, and over seventy 
