428 
APPENDIX NO. XIII. 
it shifts suddenly in the following month to Melville Island, and 
remains there during November. 
The motion of this meridian of maximum cold is therefore slowly 
to the eastward from October through the succeeding months till Sep¬ 
tember, when it suddenly recovers its westerly limit in a single month. 
The number of water-courses which separate the islands to the west¬ 
ward of Baffin’s Bay, frozen over during the greater part of the year 
and cementing together these islands, form a large area which stands 
in the same relation to temperature as an Arctic continent, and mav 
thus become one of the principal causes of the low temperatures ob¬ 
served; and this may explain the descent of the isotherms. The 
curves passing over Bank Land and Prince Patrick Island indicate by 
their curvature the presence of an open (not entirely frozen over) 
Polar sea. During the summer, the land absorbing heat more rapidly, 
we find the curves plainly pointing out the middle ice of Baffin’s Bay • 
even the so-called North Water off Wostcnholm appears to be indi¬ 
cated by the June isotherm of -f 32 °. j n September, the currents 
from the north and west (see my current-chart of Baffin’s Bay, in Dr. 
Kane’s narrative of the first Grinnell Expedition) also favor a low 
atmospheric temperature over Baffin’s Bay. The above general climatic 
outlines cannot be extended to Greenland, whose interior is as yet a 
perfect terra incognita. Proceeding along its western coast to the 
northward, we find a regular decreasing temperature, which decrease 
appears to be accelerated as we approach the latitudes of Wostenholm 
and Rensselaer Harbors. 
In the following it is proposed to give some comparative meteoro¬ 
logical detail in support of, and further illustrating, the views pre¬ 
sented in the above sketch. 
C. A. S. 
