I Tversnit XIX se vi disse Forhold igjen. Ved 
Bækkenets østlige Skraaning, hvor Trykket er mindst, se 
vi Bundvandet stige op med lavere Temperatur og Salt- 
holdighed. 
I Tversnittene XXII, XXIIT, XXIV og XXV iagt- 
tage vi fremdeles, hvorledes det samme Trykkets Maximum 
sender koldt Polarvand ned i Dybet. Ved Spidsbergens 
Banker ligger Tæthedsmaxima med synkende varmere og 
saltere Vand. 
Vi have saaledes 1 vort Nordhav to Trykmaxima, der 
sende koldt, paa Overfladen afkjølet, og ved Issmeltning 
fortyndet Vand, Polarvand, ifra Polarstrommen 1 Gronlands- 
havet og ved Jan Mayen, ned i Bækkenets dybe Partier. 
Vi have andre Trykmaxima, ved Bækkenets Sydrard og 
under 709 Bredde ved dets Østrand, der sende varmere 
saltere Vand ned 1 Dybet. Vi have Trykminima, 1 68° 
og 1 74° Bredde, der bringe det koldere og saltfattigere 
Dybvand op imod Overfladen. Disse forskjellige Stromnin- 
ger ville, paa Grændserne mellem dem, paavirke hverandres 
Vandmasser ved Afkjøling eller Opvarmning, ved Udspæd- 
ning eller Saltnmg. Men saalænge Strømmene bestaa, 
blive deres iboende Egenskaber vedligeholdt 1 den Ud- 
og 
strækning, lagttagelserne vise, og med den Virkning til at 
holde Strømningerne vedlige, som Trykfordelingen antyder. 
Efter at have studeret de verticale Bevægelser i Nord- 
havets Dyb kunne vi nu gaa over til at granske de hori- 
zontale Bevægelser i Niveaufladerne 1 de forskjellige Dyb- 
der. Overfladens Stromninger have vi allerede tidligere 
studeret og paavist deres Forbindelse med Temperaturens 
og Saltholdighedens Fordeling... 
I 300 Favnes Dyb have vi et Minimum af Tryk i en 
Strækning fra Sydvest mod Nordost mellem Jan Mayen og 
Norge (Pl. XLIV). Denne Trykfordeling betinger en cyclo- 
nisk Bevægelse omkring Minimum. Paa Østsiden bliver 
Strømmen nordgaaende, paa Vestsiden sydgaaende. Den 
første fører Vand md fra Atlanterhavet, den sidste fra 
Polarhavet. Trykkets Minimum ligger ikke centralt i Havet. 
Polarstrommens Qmraade bliver større end den atlantiske 
Strøms. Men Kartet Pl. XLIV viser, at ialfald den største 
Del af det under Grønlands Østkyst fra det indre Polar- 
hav indstrømmende Vand finder sit Afløb gjennem Dan- 
markstrædet i Lagene mellem Overfladen og 300 Favnes 
Dyb, som er Strædets mindste Dybde. Herved afsrændses 
den vestligste Del af Polarstrømmen fra Circulationen i 
Nordhavet, og denne kan foregaa omkring et nogenlunde 
centralt Trykminmum. 
Langs Nordsøbanken og de norske Kystbanker ligge 
Isobarerne for det meste paa skraa mod Isobathen for 300 
Favne. I det væsentlige maa Bevægelsen nordover foregaa 
langs Isobathen. Hvor Trykket langs denne er aftagende, 
kan man vente en opstigende Bevægelse, altsaa med Tem- 
peraturforringelse; hvor Trykket er voxende, en nedstigende 
Bevægelse med Temperaturstigning. Saadant se vi virkelig 
> te te) > 
180 
In Transverse Section XIX, we again meet with 
these conditions. On the eastern declivity of the basin, 
where the pressure is least, the bottom-water is seen to 
rise, with a lower temperature and a less amount of salt. 
In Transverse Sections XXII, XXIII, XXIV, and 
XXV, we observe the same maximum of pressure, sending 
down cold Polar water into the deep, On the Spitzbergen 
banks occur density-maxima, with sinking water, warmer 
and salter. 
We have thus im our North Ocean two pressure- 
maxima sending down cold water, cooled at the surface and 
diluted by the melting of ice — Polar water — from the 
Polar current in the Greenland Sea and off Jan Mayen, into 
the deep parts of the basin. Other pressure-maxima occur, 
at the southern margin of the basin and, in lat. 70° N; at 
its eastern margin, that send down warmer and salter 
water into the deep. We have pressure-minima in lat, 68° 
and 74° N, bringing up the water of the deep, colder and 
less salt, towards the surface. These different currents 
will act at their several limits on the mass of each other’s 
water, by cooling or by heating, by diluting or by increas- 
ing the amount of salt. But, as long as the currents 
exist, their inherent characteristics are maintained to the 
extent shown by the observations, together with the effect 
to maintain the currents indicated by the distribution of 
pressure. 
Heaving studied the vertical motions in the deep 
of the North Ocean, we can now pass on to examine the 
horizontal motions at the surfaces of level at the several 
depths. 
investigated, and shown their connexion with the distribu- 
tion of temperature and the proportion of salt. 
At a depth of 300 fathoms, we have a minimum of 
pressure throughout a tract stretching from south-west to 
north-east, between Jan Mayen and Norway (Pl. XLIV). 
This distribution of pressure determines a cyclonic motion 
around the minimum. On the east side, the current sets 
northward, on the west southward. The former branch 
from: the Atlantic Ocean, the latter 
The minimum of pressure does not 
occupy a central position im the sea. The area of the 
Polar current exceeds that of the Atlantic current. But 
the map Pl. XLIV shows that at all events the greater part 
of the water flowing in along the east coast of Greenland 
from the inner tracts of the Polar Sea, has its outlet 
through Denmark Strait in the layers between the surface 
and 300 fathoms beneath, the least depth in the Strait. 
Thus the western part of the Polar current is bounded off 
from the circulation of the North Ocean, and this can 
The currents of the surface we have previously 
carries In water 
from the Polar Sea. 
take place round a comparatively central pressure-minimum. 
Along the North-Sea Bank and the Norwegian Coast 
Banks, the isobars have in great part an oblique position 
towards the isobath for 300 fathoms. The motion north- 
ward must chiefly proceed along the isobath. Wherever 
the pressure along the isobath is found to decrease, an 
upward tendency may be expected, accordingly with a dim- 
inution of temperature; where the pressure is found to 
