92 



ward of the boundary of warm water. Since the fog sheet is found 

 habitually lying over the cold-water area, any contraction of the latter 

 means less fog south of the Grand Banks. Stripped of fog, the bergs 

 lose much of their danger. The fact that there is less fog in late 

 summer and autumn, as shown by the U . S. Pilot Chart of the North 

 Atlantic, points toward less Arctic water around the Grand Banks. 

 Other causes for less fog are the northern drift of the warm surface 

 layers under the impetus of the southerly winds, and the general 

 solar warming of the surface of the ocean, which becomes more pro- 

 nounced at this period. 



Table of data concerning scientific stations occupied by the " Tampa" and " Modoc." 



[See Chart "A."] 



