1906. No.3. AMUNDSEN’S OCEANOGRAPHIC OBSERVATIONS IN 1901. 87 
temperature will also further be slightly raised by compression, at the 
greater depths. 
It must consequently be expected that fairly uniform low temperatures 
of about or below —1:3° C., will be found in the region where the 
coldest bottom-water arises and while its formation is going on. This is to 
some extent the case at Amundsen's Stations, especially those of them 
which were taken first in the season), But it seems to have been still 
more the case at Mohn's Station 302, where the following temperatures 
were observed: 
Mohn's Station 302, Fuly 19, 1878. 
| | | 
Depth | Temperature | Depth Temperature Depth Temperatur 
o metres 30° C. 55 metres ro. © 183 metres | —r'3° C. 
18 2 30 „ 73 ” ET = 366 2 | SE ” 
37 ” oo ” or C3 A » 3630 2 —148 Lad > 
The three latter of these observations (at 183, 366, and 3630 metres) 
were taken with a Negretti and Zambra reversing thermometer, and may 
therefore be expected to be fairly trustworthy, although probably somewhat 
too low, like most Mohn’s temperatures for the deep strata of the Nor- 
wegian Sea. 
Both Amundsen’s and Mohn’s observations were, however, taken 
some months after the cooling at the surface hade ceased; and consequently 
it cannot be expected that the original conditions would be found still 
existing; for it is clear that the heavy water produced by the cooling, 
1 The fact that the surface-salinities in the region of Amundsen’s Stations 13—23 were 
rapidly decreased during the months of June and July, root, (as is proved by Amundsen’s 
numerous observations as well as by those of the Capella, see above p. 15) indicate 
that earlier in the spring the surface salinities had probably been still higher, and must 
then have been at least very near 349. After the above was written, however, 
Helland-Hansen and the present writer, for their memoir on the Norwegian Sea have 
examined several series of surface observations taken in the years 1901—1904, by 
several Captains of Norwegian sealing vessels, and it was found that in March, April, 
‘and even May, the surface salinity is always, without exception, very high in the very 
region of Amundsen’s Stations. It is as a rule about 34°9 "4, whilst the temperature 
is very low, generally near the freezing point of the sea-water (—1°9° C.). This is 
conclusive evidence that the above explanation of the origin of the bottom-water of the 
Norwegian Sea is correct (see B. Helland-Hansen and F. Nansen, Report on Norw. 
Fishery and Marine Investigations, vol. I, No. 2). 
? This temperature was observed with the Negretti and Zambra reversing thermometer. 
Two observations were also made at the same depth with two other less trustworthy 
thermometers (one Miller-Casella and one Casella-Buchanan) which gave very improbable 
values. 
