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. 
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te ae LMTZ»...”""*= 
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San LL - > 
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Fic. 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 down to 
when 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 
