* 
POLAR SEA. 547 
Sir David Brewster, by a combination of the observations of Scoresby, 
Gieseke, and Parry, determined the existence of two poies of cold, one for 
either hemisphere, and both holding a fixed relation to the magnetic poles. 
These two seats of maximum cold are situated respectively in Asia and Amer- 
ica, in longitudes 100° west and 95° east, and on the parallel of SO''. They differ 
about five degrees in their mean annual temperature ; the American, which is 
the lower, giving three degrees and a half below zero. The isothermals sur- 
round these two points, in a system of returning curves yet to be confirmed by 
observation ; but the inference which I present to you, without comment or 
opinion, is, that to the north of 80°, and at any points intermediate between 
these American and Siberian centres of intensity, the climate must be milder, 
or, more properly speaking, the mean annual temperature must be more elevated. 
Petermann, taking as a basis the data of Professor Dove, deduces a movable 
pole of cold, which in January is found in a line from Melville Island to the River 
Lena, and, gradually advancing with the season into the Atlantic Ocean, recedes 
with the fall and winter to its former position. Such a movement is clearly 
referable to the summer land currents with their freight of polar ice. 
With the consolidation of winter, the ice recedes, and the Gulf Stream enters 
more perceptibly into the far north. The mean temperature of the northeast 
coast of Siberia is forty or fifty degrees colder than that of the western shores 
of Nova Zembla, while in July it is twenty degrees higher. 
But if any point between 75° and 80° north latitude, a range sutficiently wide 
to include all the theories, be regarded as the seat of the greatest intensity of 
cold, we may, perhaps, infer the state of the Polar Sea from the known temper- 
atures of other regions, equally distant with it from this supposed centre ; 
though, as the lines of latitude do not correspond with those of temperature, 
this must be done with caution. 
I have been interested for some time in examining this class of deflections ; 
and I find that they point to some interesting conclusions as to the fluidity of 
the region about the pole, and its attendant mildness of weather. 
Thus, for instance, at Cherie Island, surrounded by moving waters, but in a 
higher latitude than Melville Island, the seat of the greatest observed mean an- 
nual cold, the temperature was found so mild throughout the entire Arctic win- 
ter, that rain fell there upon Christmas-day. 
Barentz, a most honest and reliable authority, speaks of the increasing warmth 
as he left the land to the north of 77°. The whalers north of Spitzbergen con- 
firm the saying of the early Dutch, that the " Fisherman's Bight" is as pleasant 
as the sea of Amsterdam. 
Egedesminde and Rittenback, two little Danish and Esquimaux settlements 
on the west coast of Greenland, in latitude 70°, with a climate influenced by 
adjacent land masses, but nevertheless not completely ice-bound, are in the 
isothermal curve (summer curve) of 50°, giving us a vegetation of coarse grass- 
es, and a few crucifers. 
In West Lapland, as high as 70°, barley has been, and I believe is still grown ; 
though here is its highest northern hmit. If 80° be our centre of m.aximum 
cold, the pole, at 90°, is at the same distance from it as this West Lapland 
limit of the growth of barley ! 
But there are other arguments based upon known facts, and facts popularly 
recognized, bearing upon the theory of an open sea : 
