OCEANOGRAPHY OF SEA OF GREENLAND—DAMAS. 375 
and those of Norwegian sealers, it has become possible to construct 
for the summer of 1905 very complete maps showing the condition 
of the ice in the Greenland Sea. As an illustration we give here 
the maps for the months of July and August (figs. 2 and 3). They 
enable us to determine some of the chief laws of ice distribution. 
The land ice is attached on the west to the Greenland coast. Its 
exterior limits exceed but little the shallow depths of the conti- 
nental plateau. 
The eastern limit 
of the polar ice cor- 
responds rather 
closely with the 
isobar of 1,500 me- 
ters which marks 
the base of the con- 
tinental talus slope; 
that is to say, the 
field which it 
covers iS enor- 
mously expanded 
toward the north 
and gradually nar- 
rows to the south 
until, at the height 
of the second cross- 
ing of the Belgica, 
the zone has 
scarcely, according 
to observations of 
Commander de we Continuous pack-(ce 
Gerlache, an extent wm fand- fee”, 
wes farge (ce fields 
of more than 2 or oe Solid pack -(ce 
3 kilometers. The 6% oper pachice 
distribution of the ‘1! 3.—Map showing the distribution of ice in Greenland 
‘ Sea in August, 1905. 
polar ice on the 
surface is, then, closely related to the topography of the ocean bottom. 
The bay ice covers a surface varying with the season. It occupies 
in general the central or region of most profound depth of the Green- 
land Sea. Its progressive retreat in summer is irregular. In gen- 
eral it is less rapid immediately to the south of Jan Mayen than 
farther to the north. There results from this the formation of a 
gulf sufficiently constant to merit the name of Gulf of Bay Ice, 
which the Norwegian hunters have given it. It is through pene- 
45745°—sm 1909——25 
