216 



bulletin: museum of comparative zoology. 



The first (Fig. 56), from the southern part of the basin of the Gulf 

 of Maine (Station 10058), to the outer edge of the continental shelf 

 (Station 10061) shows that there was very little difference in density, 

 depth for depth, on the two sides of Nantucket Shoals, above the level 

 of the latter (about thirty fathoms) . Below that level the water was 

 distinctly lighter on the south than on the north side of the Shoals; 

 and the vertical stability of the water was very slight over the outer 

 part of the shelf between the thirty-five and fifty fathom levels. 



Fig. 56. — Density profile from the southern part of the basin of the Gulf of 

 Maine (Station 10058) across Nantucket Shoals, to the continental slope 

 south of Nantucket (Station 10061) July 8-10. 



The next profile (Fig. 57) from Station 10063, off Nantucket, to the 

 edge of the continental shelf (Station 10061), shows that douTi to 

 about twenty fathoms the water was considerably lightest at the 

 shore end. Below thirty fathoms the density curves dip seaward, 

 especially at the outer edge of the shelf, coincident with the cold 



