é 
252 Review of the Results of the U. S. Coast Survey. 
One hundred and thirty-six miles from the coast occurs another 
range of hills fifteen hundred feet high and twenty-eight mi 
base toward the shore, and six hundred feet high with a base of 
about seventeen miles on the outer side. Beyond this there isa 
more gradual rise. Now the forms of the curves of equal tem- 
perature resulting from multiplied observations at different depths 
along the section correspond exactly to the outline of the bottom, 
Perhaps the most remarkable peculiarity of the Gulf Stream 
is what has been appropriately termed the “cold wall,” a mass 
of cold water lying between the warm water and the shore, and 
sharply defining the inner boundary of the great current. the 
change from the warm water of the stream to the cold body 
of water inside of it toward the shore, is particularly sudden and 
well marked in the northern sections, but may also be easily 
distinguished south of Cape Hatteras. In the cold water m- 
shore from the Gulf Stream a current setting southward has 
been observed, as also in the cold band outside the axes.  Itis 
fath- 
oms beneath the surface, there is, as a general rule, an increase of 
The underlying polar currents are as distinctly marked in ” 
southern as in the northern latitudes. Thus in latitude 87° 2 
this place that the most recent observations fully con re 
theory of Franklin that the Gulf Stream makes a complete X- 
cuit in the Atlantic, returning again to its jah ie pie? 
e coasts © 
Treland and Norway, and is thence reflected toward the Ane 
ocean. This branch appears to offer the most feasible passag® 
