Kartet over Havoverfladens aarlige Middeltemperatur 
(Pl. XVI) viser, at dennes Fordeling er afhængig, foruden 
af Bredde», i højeste Grad af Kysternes Retning. Paa 
mange Steder lobe Isothermerne nærmere langs Meridia- 
nerne end langs Parallelerne. Det characteristiske for Iso- 
thermernes Løb er deres Tungeform, og Tungernes Spid- 
ser pege paa forskjellige Steder i forskjellige Retninger. 
Den højeste Temperatur findesi Kartets sydvestlige Hjørne, 
hvor Isothermen for 119 optræder. Den laveste Tempera- 
tur findes i Grønlandshavet, hvor Isothermen for 0° løber 
parallel med dettes omtrentlige Grændse, og i den nordre 
Del af Østhavet mellem Spidsbergen og Novaja Semlja: 
I begge Have betegner Nulgrads-Isothermen den omtrentlige 
midlere Isgrændse. Isotherm-Tungernes concave Parti an. 
giver ved sin Rækkefølge 1 Almindelighed den Hen, hvor- 
fra Stedets Temperatur har sit Udspring, forsaavidt den er 
et Resultat af Stromninger. Man kan saaledes tale om 
varme og kolde Isotherm-Tunger. En Linie, der forbinder 
de successive Tungespidser, bliver en Varme-Axe eller en 
Kulde-Axe, der har den Egenskab, at i begge Retninger 
tvers paa Axen, saavel til Højre som til Venstre, er Tem- 
peraturen i Overfladen respective synkende eller stigende. 
En Varme-Axe kan forfølges fra Atlanterhavet vesten- 
for Skotland, mod Færø-Island-Ryggen, langs denne mod 
Islands sydostlige Hjørne. Som dens Fortsættelse kunne 
vi betragte den langs Islands Vestkyst og Nordkyst gaaende 
Række af varme Tunger. 
En anden Varme-Axe udgaar fra den forrige vesten- 
for Færøerne og tager Vejen nordenom disse Øer mod Øst 
ved den 63. Breddegrad, hvor den slutter sig til den nest 
følgende. 
Denne udgaar fra samme Sted som den første, bøjer 
mod Øst nordenfor Orkenøerne, passerer Shetland og gaar 
herfra udenfor den norske Vestkyst. Udenfor Lofoten sen- 
der den en Arm mod Vest henimod Jan Mayen; under den 
70. Breddegrad sender den en Arm nordover, der løber 
langs Spidsbergens Vestkyst helt op til den 80. Bredde- 
grad, og en tredie Arm følger Norges Kyst østenfor Nord- 
kap og den Murmanske Kyst til det Hvide Hav og Novaja 
Semlja. 
En Varme-Axe sees ogsaa i Syd for Jan Mayen, 
gaaende mod Nordvest op paa Vestsiden af denne Ø. 
En Kulde-Axe er antydet fra den nordlige Del af 
Østhavet henimod Spidsbergens Sydkap og Beeren-Eiland. 
En anden fra Grønlandshavet mod Sydost omtrent 
midtvejs mellem Spidsbergen og Jan Mayen. 
En tredie østenfor Jan Mayen. 
En fjerde fra Grønlandshavet mellem Jan Mayen og 
Island, udenfor Islands Østkyst og videre mod Sydost til 
«I 
The Map giving the Mean Annual Temperature of the 
Sea-Surface (Pl. XVI), shows the distribution to be depen- 
dent, not only on the latitude, but also, in the highest 
degree, on the direction of the coast. In many localities, 
the isotherms run closer along the meridians than they do 
along the parallels. The most prominent characteristic 
distinguishing the course taken by the isotherms, is their 
linguiform shape, and the tip of the tongue points in differ- 
ent places in different directions. The highest temperature 
is seen to occur in the south-western corner of the map, 
together with the isotherm for 11°. The lowest tempera- 
ture occurs in the Greenland Sea, where the isotherm for 09 
runs parallel to the approximate limit of the latter, and 
} in the northern tract of the Barents Sea, between Spitzber- 
gen and Novaja Semlja. In both seas, the isotherm for 0° 
marks the approximate mean limit of ice. The concave 
part of the linguiform isotherms generally points towards 
the tract from. which the local temperature has its origin, 
provided it result from the action of currents. Hence, we 
can speak of warm and cold isothermal tongues. A line 
connecting the extremities of the linguiform 
parts, constitutes an axis of heat or of cold, with the prop- 
erty, that in both directions perpendicular to such an 
axis, alike to the right and to the left, the temperature 
successive 
at the surface is respectively falling or rising. 
An axis of heat may be traced from the Atlantic, 
west of Scotland, to the Færoe-Iceland Ridge, and along 
the latter towards the south-eastern extremity of Iceland. 
As its continuation, we may regard the series of warm 
isothermal tongues extending along the west and north 
coasts of that island. 
Another axis of heat strikes off from the preceding, 
west of the Feroes, and makes its way north of those 
islands towards the east, at the 63rd parallel of latitude, 
where it joms that next in succession. 
This axis extends from the same point as the first, 
makes a bend to the east north of the Orkney Islands, 
and passes Shetland, proceeding thence towards the 
West Coast of Norway. Off Lofoten it sends off an arm - 
westward, in the direction of Jan Mayen; at the 70th 
parallel of latitude it sends off an arm northward, which 
extends along the west coast of Spitzbergen, as far as the 
80th parallel of latitude; and a third arm follows the coast 
of Norway, east of the North Cape, and the Murman 
coast, to the White Sea and Novaja Semlja. 
An axis of heat also extends south of Jan Mayen, 
passing towards the north-west up along the west side of 
that island. 
An axis of cold is found to proceed from the north- 
ern part of the Barents Sea towards South Cape, Spitz- 
bergen, and Beeren Eiland. 
Another extends from the Greenland Sea towards 
the south-east, about midway between Spitzbergen and 
Jan Mayen. 
A third occurs east of Jan Mayen. 
A ‘fourth passes from the Greenland Sea between 
Jan Mayen and Iceland; off the east coast of the lat- 
