Lakge-Scale Features 



25 



It was the close correspondence of the current charts (see fig. 2) and 

 the surface-temperature charts (see figs. 3 and 4) which stimulated the 

 interest of early seafarers in ' thermometric ' navigation so many years 

 ago (see Chapter I). 



SURFACE TEMPERATURE 



DEGREES FAHRENHEIT 



AUGUST 



Fig. 4. Contours of surface temperature in the western North Atlantic for 

 August, according to Fuglister (1947, pi. 8). 



THE DISTRIBUTION OF PROPERTIES WITH DEPTH 



An average temperature sounding (with depth) for two seasons of the year, 

 and on both sides of the Gulf Stream, is shown in fig. 5, a. The curve marked 

 'slope' is the sounding made in the slope water between the continental 

 shelf along the coast and the Gulf Stream near Chesapeake Bay ; the curve 

 marked ' central ' corresponds to a sounding in the North Atlantic Central 



