KR 
OOO. Trykket 1 det dybeste Punkt B vilde være det 
samme 1 alle Rør, og Højden OB vilde forholde sig til 
Hojden OB’ som Tætheden 1 OB’ til Tætheden i OB. 
Overfladen OOO vilde være en Ligetryks-Flade. I det 
dybeste Punkt B vilde Ligetryksfladen B’ BAB” falde sam- 
men med Niveaufladen. I en mellemliggende Dybde vilde 
en Ligetryksflade 000" have en Krumning i Forhold til 
Niveaufladen, der ligger mellem Overfladens og Bundens. 
I alle Niveauer ville Ligetrykstladerne løfte sig mod Randen 
og sænke sig mod Midten. Denne Ligetryksfladernes Af- 
vigelse fra Niveaufladerne vilde være sterkest i Overfladen, 
og aftage stadigt mod Bundens dybeste Punkt, hvor den 
bliver Nul. 
Tænkte man sig nu alle Rørvægge pludselig forvand- 
lede til Vand, af samme Tæthed som de nærmeste Vand- 
lags, vilde Overfladen O00 ikke længere kunne bestaa. 
Den vilde i ethvert Punkt, undtagen i Midtpunktet, have 
en Heldning mod den gjennem Midtpunktet gaaende Niveau- 
flade nOn. I denne sidste blev Trykket ikke constant, men 
desto større, jo længere Punktet ligger fra det dybeste Punkt 
eller Centret. Enhver Vandpartikkel i Overfladen vilde 
være underkastet et Overtryk udentra indad mod Centrum, 
og som Følge deraf stræbe at bevæge sig henimod dette. 
Det samme vilde i det første Øjeblik finde Sted i 
alle Ligetryksflader. Gjennem hele Vandmassen vilde der 
opstaa en Strømning mod Midten. 
- Virkningen af denne Strømning er, at Fordybningen 
i Havoverfladen formindskes. Istedetfor Overfladen OOO 
faa vi en mindre concav Overflade TTT. 
Men herved er Trykkenes Fordeling i Dybet bleven 
forandret. I Fladen TTT ere Skraaningerne mod Niveau- 
fladen mindre end før, og Trykforskjellerne mindre, men 
Trykket er fremdeles mindst 1 Midten. I Niveaufladen 
BBB’ var før constant Tryk, nu er Trykket voxet i Punk- 
tet B, over hvilket Vandmassens Højde er forøget, og sun- 
ket i Punkterne DB’, over hvilke Vandhøjden er formindsket. 
depressed in the middle. If, in the annexed figure 1, 
NNN represent a surface of level, the surfaces of the water 
in the tubes would coincide with the surface OOO. The 
pressure at the deepest point, B, would be the same in all the 
tubes, and the height OB would bear the same ratio to the 
height OB’ as the density in OB’ to the density in OB. 
The surface OOO would be a surface of equal pres- 
sure. At the deepest point, 6, the surface of equal pressure, 
BBB’, would coincide with the surface of level. In an 
intermediate depth, a surface of equal pressure, O'0'0’, 
would, compared with the surface of level, have a curvature 
lying between that of the surface and that of the bottom. 
In all levels, the surfaces of equal pressure would rise towards 
the margin and sink towards the middle. This deviation 
of the surfaces of equal pressure from the surface of level 
would be greatest at the surface of the sea, and gradually 
diminish towards the deepest point of the bottom, where 
it is nil. 
Now, were the walls of all the tubes suddenly trans- - 
formed into water of the same density as that of the 
nearest water-stratum, the surface 000 could no longer 
exist. It would, at every point save the mid-point alone, 
exhibit an inclination to the surface of level, nOn, passing 
through the mid-point. At the latter surface the pressure 
would not be constant, but the greater the farther the 
point lay from the deepest point or from the centre. Every 
particle of water at the surface would be subjected to a 
pressure from without to within towards the centre, and 
hence tend to move in that direction. 
The same would take place in the first instance at 
all surfaces of equal pressure. Throughout the whole 
body of water, a current would arise setting towards the 
central part. 
The effect of this current is to diminish the depres- 
sion in the sea-surface. 
get a less concave surface, TTT. 
But this changes the distribution of pressure in 
the deep. Throughout the surface TTT, the inclinations 
to the surface of level have diminished and the differences 
in pressure become less, though the pressure still con- 
tinues least in the middle. Throughout the surface of 
level, B’ BB’, the pressure had previously been constant; 
now, the pressure has increased at the pomt B, above 
In lieu of the surface OOO, we 
