184 
A VOYAGE TO SPITZBERGEN. 
and clear spaces in the drift-ice being quite insuffi¬ 
cient to make up for the space left by the ice during 
the summer. The great abundance of animal life in 
the waters of the highest latitudes reached indicates 
that the water is not ice-cold; and the migration of 
numerous species to the north of 80 ° shows that 
the means of subsistence can be obtained. There is 
reason to believe that whales occur far to the north 
of 80 °; and if so, there must necessarily be suffi¬ 
cient open water to allow of their finding ready access 
to air. 
In the Spitzbergen seas a blue, cloud-like appearance 
is well known as a sign of open water; and this has 
been seen on the distant north horizon even by ships 
which have been beset by ice in the highest latitudes. 
Icebergs, it is well known, waste more rapidly below 
the surface than in the air, causing them to topple 
over frequently, obviously the effect of the warm 
current. 
The question, then, is, from whence do the warm 
waters come ? and how do they acquire their heat? 
And this is one of the questions which a polar voyage 
by way of Spitzbergen would almost certainly eluci¬ 
date. Another important subject of investigation would 
be the conditions under which’the prevalent north 
winds of high latitudes originate. There is one argu¬ 
ment bearing upon the temperature of the circumpolar 
