338 W. Hopkins on Changes of Climate. 
34: It is probable that every great oceanic current must have 
its counter-current. Now, if the mass of water constituting the 
Gulf-stream were poured, as here supposed, directly into the Are- 
tic Ocean, the only course, which any great counter-current from 
that ocean could follow, would seem to be through the North Sea 
intervening between the coasts of Norway and Greenland, and 
across the submerged portion of northern Europe. There would 
in fact be no other considerable opening from the north ; for even 
if we suppose the low lands of northern Asia to be submerged, 
the mountain-ranges of that region would still offer an insupera- 
ble bar to any egress, except in the direction above indicated, for 
the waters of the Arctic Ocean. The opening through Behring’s 
Straits would probably not be worthy of notice. ‘These consid- 
erations appear to me to increase considerably the probability that 
this diverted course of the Gulf-stream would be attended by a 
cold current over the region now occupied by the continent of 
northern and western Europe. : 
35. The theory which I have here proposed respecting the di- 
version of the Gulf-stream, is not to be regarded as resting on ap 
hypothesis framed simply to enable us to account for a particular 
class of phenomena. I regard it, on the contrary, as resting 0n@ 
necessary inference from the submergence of the North Ameri 
can continent ; for, I repeat, if that continent were submerged to 
the depth implied, as I believe by the most conclusive geological 
evidence, the course of the Gulf-stream could be no other that 
it is by no means necessary to extend the supposition to the 
of the land was sufficient to admit the current to the Arctic Sea, 
or after its course had been again impeded, or altogether — 
ui 
t would 
doubtlessly, as I have above remarked, increase, and probably 
very much increase, the temperature of the region corresponding 
to the present shores of the Arctic Sea; for nearly the whole 
that mass of warm water, which now elevates so remarkably 
temperature of the northern Atlantic up to the North Sea, ob 
then proceed to discharge itself into the Arctic Sea between t 
Rocky Mountains and Hudson’s Bay, by a course shorter, oa 
direct, and probably therefore more rapid, than that by which . 
now reaches the coast of Iceland. I should consider I mos 
probable that it would produce a temperature in the regio8 cond 
the northeastern flank of the Rocky Mountains, and extending 
