1906. No.3. AMUNDSEN’S OCEANOGRAPHIC OBSERVATIONS IN 1901. 15 
In the first days of June there were surface-salinities of about 34'8 %/00 
in the region of Amundsen’s Stations ıı and 12, whilst only a month later 
the salinities in the same region had, according to the observations of 
Capt. Støkken of the Capella, sunk to about 34°52, 34'01, and 33°52 %00. 
On August 1st, 1901, Capella also crossed Amundsen's route, and 
where the latter found salinities about 3452/00, on June 5, 1901, there 
was 33'37 09/00 then, two months later. In July, 1901, Dr. Knipowitsch 
also crossed Amundsen’s route at several places (see Pl. I), and he every- 
where found much lower surface salinities than the latter found in April, 
May, and the beginning of June. Æ. g. in about 74°30’ N. Lat. and 
33° 30’ E. Long., Amundsen found, on June 6, 1901, about o'o° C. and 
34'56 %00, whilst Knipowitsch a little more than a month later found 
about 1° C. and below 34'0 Yoo!. And near 74° N. Lat. and 40° E. Long. 
Amundsen found on June 5, 1901, — 0'8° C. and 34°44 %/00, whilst Knipo- 
witsch found in July about 1° C. and below 33'000, etc. 
In the sea west of Spitsbergen there are similar although much smaller 
differences between the observations of the Jasai and the Hvidfisken in 
June and those of Amundsen in July and August. 
In the sea north of Jan Mayen, in the region of Amundsens Stats. 
13—23, similar and very prominent changes occurred during June and 
July, 1901, as is seen if Amundsens observations from the end of June 
be compared with those he took later in the same region. 
South of Bear Island the conditions seem to be rather complicated 
and to change rapidly. In June, 1901, Amundsen there found tempera- 
tures about or below zero, and salinities between 34°62 and 34'94 900, 
whilst Dr. Hjort, with the Michael Sars, a little more than a month later, 
found in the same region temperatures between o'7 and 2'7° C., and 
salinities between 34°52 and 34°69 Yo. 
The explanation of this general reduction of salinity is probably that 
at the end of the winter the surface salinity of these cold regions of the 
sea has, as a rule, attained its maximum, owing to the formation of ice 
at the surface, in the same region during the winter. During the summer 
this ice is again melted, and the surface-salinity accordingly reduced. 
It is also seen that the density of the sea surface is, in these cold 
regions, very much higher in the beginning of the summer, than later, 
not only owing to the lower temperature but also as a result of the higher 
salinity. And whilst, at the end of the winter, the cold surface-water of 
the ice-forming region has, as a rule, a higher density than that of the 
1 According to Knipowitsch’s section, Ann. Hydr. u. Marit. Meteor. 1905, Pl. 6, Fig. 2. 
