CHAP. 111. } THE CRUISES OF THE ‘ PORCUPINE, dicta 
years and work, and this last task, on which he had 
entered with keen interest, must be finished by other 
hands. 
It will be seen that the bottom-temperature of the 
cold area, at 500 fathoms, does not differ by more 
than two or three degrees from that of the warm 
area, at depths beyond 1,500 fathoms. It seems, in 
fact, as Dr. Carpenter has well pointed out, as if all 
the extreme climatal conditions which, in the deep 
water of the Atlantic, are extended over a vertical 
distance of two or three miles, are here compressed, 
without greatly altering their proportions, into the 
compass of half a mile. We have the same surface 
super-heating and rapid fall for the first short dis- 
tance ; the same hump on the curves, indicating the 
presence of a layer of water heated by some other 
cause than direct solar radiation; the same rapid fall 
through ‘a stratum of intermixture ;’ and, finally, 
the same long excessively slow depression through a 
deep bottom bed of cold water nearly at a uniform 
temperature. 
As might be anticipated, if the view be correct 
that arctic conditions are in a broad sense con- 
tinuous throughout the abyssal regions of the sea, a 
large number of the inhabitants of the ‘ cold area’ are 
common to the deep water off Rockall and as far south 
as the coast of Portugal; but the fauna of the Feroe 
channel includes, besides these generally distributed 
forms, an assemblage of species—for example, the 
large crustaceans and arachnida and some of the star- 
fishes—which are not only generally characteristic of 
frigid conditions, but specially of that part of the 
arctic province represented by the seas of Spitzbergen, 
K 2 
