Hydrography of the Stream 



63 



Indeed, the T-S diagrams (see fig. 37) of water masses below 500 m. on 

 opposite sides of the Stream are so similar that it seems very likely that 

 in deep water such a transfer occurs. The large eddies which detach from 

 the Stream, as exemplified by the eddy observed on the Multiple Ship 

 cruise of June, 1950, certainly effect a transfer of water across the Stream. 

 It should be noted that they are rather solitary phenomena in the Gulf 

 Stream, at least so far as we now know. For example, in June, 1950, there 

 was only one eddy in the process of detachment in a distance of more than 

 1200 miles along the Stream. The wavelike meanders may transfer momen- 



3500 



8 3600 



18- 



14- 



10- 



6 - 



Fig. 37. Comparison between the mean temperature-salinity correlation 

 curve for the slope water and that for the Sargasso water, on the Atlantis 

 sections from Chesapeake Bay to Bermuda. From Iselin (1936, fig. 23). 



turn, but not heat and salt. A transfer of properties across the Stream on 

 a scale smaller than that of these large eddies does not appear to be 

 indicated. Ford, Longard, and Banks (1952) have called attention to a 

 narrow band of fresh cold water extending from the surface to a depth of 

 about 400 ft., and located within the left-hand side of the Stream. Fig. 38 

 shows a bathythermograph section through such a filament of cold fresh 

 water. Ford et al. point out that of the ninety-seven crossings of the 

 Stream made in June, 1950, fifty-seven show the cold layer. It is quite 

 possible that on the other crossings the bathythermograph lowerings 

 missed the cold layer altogether — it appears to be a very slender ribbon, 

 not more than about 5 miles wide. Fig. 39, from Ford et al., shows the 



