212 DISCOVERY REPORTS 



certainly it seems it has only been used once or twice (with some small success) where these masses 



perhaps may be. 



No doubt the shortness of our vertical hauls contributes something to the scarcity of the eggs we 

 find, and it may be that the gatherings of our towed silk nets, comparatively few of which have yet 

 been examined, will reveal substantially larger numbers. I did, however, make a special point of 

 examining the catches of our oblique silk nets (N70B), wherever five or more eggs were encountered 

 in the vertical series, in the expectation that these longer-term hauls, lasting 20 min. in the surface 

 ( 1 00-0 m.) layer and for half-an-hour at deeper levels, would give better results. They have not in 

 fact done so. Some it is true have produced larger samples, but not significantly larger, none, how- 

 ever, throwing any further light on where the masses of the eggs must be and none yielding the sub- 

 stantially larger samples one would expect from nets fished for so long. The majority in fact show fewer 

 eggs than the vertical nets, or none at all, and since the oblique nets do not fish precisely the same water 

 as the vertical nets, there would appear to be a distinct possibility that such few sinking eggs as we 

 have been sampling are rather limited in lateral spread. At Station 540, for instance, where we struck 

 one of the largest recorded concentrations of eggs in our vertical nets, there were four at 50-0 m., 

 52 at 100-50 m. and 478 at 250-100 m. In the obhque (155-0 m.) net fished at the same station, but 

 not quite in the same water, there were only 15. If the eggs sampled here in those 250 sec. had in fact 

 been widely distributed, both horizontally and vertically, then the oblique net fishing for 1 2 times as long 

 in a substantial part of the same vertical horizon would surely have sampled them with conspicuously 

 greater success. A possible flaw in this argument, however, is that they might have been largely con- 

 fined to a narrow horizontal stratum and so would not in any case have offered all that much better a 

 target for the oblique than for the vertical net. 



SPEED OF THE COLD BOTTOM WATER 



It has long been thought that the movement of water in the deep sea, especially near the bottom, is 



virtually absent or extremely slow. The recent work of Swallow and Worthington (1957; 1961), 



however, below the Gulf Stream has revealed, on the bottom itself, a surprisingly strong movement, 



and although as yet no direct measurements have been made below the Weddell Sea there is historical 



evidence that there too the bottom water may be travelling faster than has hitherto been supposed. 



In March 1843 Sir James Clark Ross in the 'Erebus' and 'Terror' (Ross, 1847, vol. li, p. 363) and 



in the same month 61 years later W. S. Bruce in the ' Scotia' (Bruce, 191 1, pp. 156-7) both experienced 



what clearly must be supposed to have been abnormal interference with their deep-sea gear, Ross 



when sounding near 68° 14' S, 12° 20' W, Bruce when dredging near 71° 22' S, 16° 34' W. Both 



positions are located in deep water in the eastern part of the Weddell Sea, not far from the Coats 



Land-Princess Martha coast and directly over where some of the coldest bottom water is now known 



to lie. Ross, the pioneer, recounts his experience in the following passage. 'After a gentle air from 



the S.W., which dispersed the clouds, it fell perfectly calm; and the swell having subsided, the boats 



were lowered to try for soundings. Owing to our having always struck ground in less than two thousand 



fathoms in other parts of the Antarctic ocean, we, unfortunately, had only four thousand fathoms of 



line prepared, the whole of which ran off the reel without reaching the bottom'. He did not suspect 



that anything had gone wrong and for long this sounding of '4000 fathoms no bottom', or Ross Deep 



as it came to be known, was accepted as the deepest ever to be recorded in the Antarctic.^ It was not 



1 In a world map compiled by J. G. Bartholomew for Mill (1903) the Ross Deep, on the evidence of this single sounding, 

 appears as an enormous area of water deeper than 4000 fathoms far south in the Weddell Sea, covering 20° of meridian 

 between 65° and 70° S. It appears again conspicuously as the 'Fosse de Ross' in Richard's bathymetric chart of the Atlantic 

 published in 1907. 



