653 
of Edinburgh, Session 1881 - 82 . 
In the diagram (fig. 1) given on page 5, we have represented 
that the basin on the right is filled with water . of a uniform 
temperature, which is believed to have flowed over the top of the 
ridge (A), so that the minimum temperature in this basin is found 
at a depth the same as that over the top of the submarine ridge. 
In the Faroe Channel, however, as is shown in the diagram here 
given (fig. 2), although the water on the one side of the ridge is 
Fig. 2. 
warmer, at depths exceeding 200 fathoms, than that on the other 
side, yet on both sides of the ridge the minimum temperature is only 
reached at the bottom ; the water in the right hand basin cannot, 
therefore, have passed over the ridge, as in the case illustrated by 
diagram fig. 1. Indeed we have shown that the cold water at the 
bottom of the N.E. basin must come from the Arctic Ocean or 
Spitzbergen Sea. 
Along the whole eastern side of the Atlantic, from the island of 
Teneriffe to the Faroe Islands, the isotherm of 40° is at a depth of 
no less than 900 fathoms from the surface. If we except the enclosed 
areas of the Mediterranean, Red Sea, and Sulu Sea, this is the only 
part of the world where so high a temperature is found at so great a 
depth. 
It is owing, doubtless, to the comparative shallowness of the water, 
that the minimum temperature on the Atlantic side of the Wyville 
Thomson Ridge is so high. We have every reason to believe that if 
the depth here exceeded 2000 fathoms the minimum temperature 
would be 36*5°, as in the whole eastern basin of the Atlantic. 
What becomes of the underflow of cold arctic water shown by the 
