Notes on the sea-ice along the east coast of Greenland. 203 
all winds from a direction south of E—W will open the pack and 
clear out the coastwater, if the conditions of the ice are nearly 
normal. 
Calm weather has as a rule the same effect as southerly winds, 
viz: of causing the ice to open up, and the explanation of this may be 
sought in the theory advanced by PETTERsSon!, that the melting of the 
ice will form a local current away from the individual floes. 
The pack-ice. 
The large body of the ice between the east coast of Greenland and 
the open water has since the time of ScorEesBy jun. (who gave a good 
general description of it, chiefly based on personal observations and 
experiments) been subject to much speculation, not only among the 
men, who either sailed along or between it for purposes of hunting or 
scientific research, but also among men of science, who have attempted 
to generalize the now rather plentiful and equal mass of material. 
In the following an attempt will be made to collect this material, 
together with the reliable observations on the state of the ice, which 
since 1894 have been carried on and published at the initiative of 
the Meteorological Institute of Copenhagen. From these observations 
which cover a span of nearly twenty years, besides stray information 
gathered from other sources, some rules can be deduced which will be, 
if not correct — the space of time is of course too short for that — at 
least so universal that they may form the basis of further gene- 
ralisations. 
As the northern hemisphere is unnavigable during a great part of 
the year, and the sealers etc. leave it, even before this period falls in, 
it is only natural that the information regarding the outer edge of the 
ice is limited to the months of April, May, June, July and August. 
The position of the outer edge of the pack-ice variates considerably 
according to the seasons, and all the material, which can safely be used, 
has been collected in order to make this variation plain?. 
The outer limits of the pack-ice for the months of April, May, June, 
July and August are shown on the accompanying map (PI. V), which 
shows the mean ice-limits for nineteen years. It will be noticed that 
the edge of the ice only recedes very little from April to May, a little 
more from May to June, still more from June to July, and again only 
very little from July to August. 
The real extent of this decrease of the ice-belt is more evident when 
t5Y mer. Vol. 1900;, раз. 173. 
” Ice-observations during all the years from 1894—1913 (inclusive), as well 
as ice-limits of all recent expeditions and stray information gathered from 
sealers. 
