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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 70 



dinary tongue-like projections of the isotherms, not only at the 

 surface of the ocean but in the underlying deeper layers. These 

 come plainly into our charts (pis. i to 14) of the surface tempera- 

 ture in February and March in the different years, and also in 

 the chart (fig. 5) where we have endeavored to give particular 

 attention to these tongue-like features of the isotherms in the 

 month of February for the interval which we have investigated. 



Of particular interest are the current relations in the remark- 

 able cold " wedge " which, as already has been said, penetrates 



Figure 5. Average temperature of the ocean's surface in February, 1900 

 to 1910. 





Figure 6. A schematic representation of the currents on the surface of the 

 North Atlantic Ocean according to our understanding of them based princi- 

 pally upon the distribution of temperature and in part on the salinity. 



southward into the warm water masses of the Gulf Stream, between 

 49° and 50° west longitude, and extending to the south of 40° 

 north latitude. As is shown in our isotherm chart, figure 5, this 

 " wedge " is exactly in the region of the most southerly corner of 

 the Newfoundland Banks. This can be seen from the isobaths 

 for 200 meters and for 1,000 meters appearing in figure 5. The 

 " wedge " forms, so to say, a continuation of this corner towards 

 the south, and follows essentially the course of the isobath for 

 4,000 meters as it makes its tongue-like extension towards the 

 southeast (see fig. i). During the Michael Sars expedition in the 

 year 1910, a section of this " wedge " was taken (see Murray and 



