UT 
17°.5 
Maade som Havtemperaturerne til Construction af Karter 
over dens Fordeling i Overfladen og ved Bunden samt af 
verticale Tversnit. Disse tilsammen fremstille den specifi- 
ske Vægts eller den dermed proportionale Saltholdigheds 
Fordeling i horizontal og vertical Retning 1 Nordhavet. 
Under dette Arbejde viste der sig enkelte Uregelmæssig- 
heder, som maatte elimineres, og som jeg her skal gjøre 
Rede for. 
Udenfor Norges Kyst fra Stad til Lofoten give de 
directe Observationer, som Tornøes Kart viser, i Overfladen 
meget bugtede Linier for lige Saltholdighed. Disse har 
jeg troet at burde udjevne, og jeg har trukket mine Linier 
(Pl. XXXIV) langs Kysten uden videre Krumninger. Be- 
stemmelserne af den specifiske Vægt i Overfladen ere gjorte 
med Vand fra Overfladen selv. I denne kunne forskjellige 
Aarsager, som Nedbør, sterk Fordunstning, let fremkalde 
locale og temporere Afvigelser fra den normale Salthol- 
dighed*. 
I 1877 og 1878 er Saltholdigheden bestemt saavel 
ved Aræometer som ved Chlormengden. Som man af 
Tornøes Tabeller ser, stemme Resultaterne af disse Frem- 
gangsmaader 1 Almindelighed meget vel overens. I disse 
Tilfælder har jeg taget Middeltallet af begge, idet jeg, 
efter Tornøes Methode, først omgjorde Tallene i hans Ru- 
specifiske Vægt ved har jeg benyttet paa samme 
brik *Saltmængde efter Chlormængde” til spec. Vægt v. 
17015 a0 
TOR Paa nogle faa Steder er der større Afvigelser mellem 
Aræometer- og Chlorbestemmelserne. Ved Hjelp af Kar- 
terne og Tversnittene kunde jeg strax se, hvilken af disse 
Bestemmelser der sluttede sig bedst til det af de øvrige 
Observationer givne System, og denne blev da valet, med 
Udelukkelse af den anden, enten denne var Chlorbestem- 
melse eller Aræometerbestemmelse. 
Da det var af Interesse at udvide Systemet til for- 
skjellige Dele af Nordhavet, som vor Expedition ikke kom 
til at besøge, har jeg søgt at udfylde det ved Hjelp af 
Tagttagelser fra andre Expeditioner. I første Række 
staar her den anden tyske Nordfart?. Da Aræometer- 
observationer fra forskjellige Expeditioner, ialfald de tid- 
ligere, ikke uden videre kunne sammenstilles. med mindre 
de benyttede Instrumenter — hvad her ikke er Tilfældet — 
ere blevne directe sammenlignede, og da det let kan hænde, 
at det System, som et Aars Observationer giver, er noget 
forskjelligt fra et andet Aars — hvad der i det foreliggende 
Tilfælde synes at finde Sted — har jeg anstillet en directe 
Sammenligning mellem de tyske Observationer fra Overfla- 
den og de norske for Strækningen fra Nordsøen til Jan 
Mayen. Den fundne Forskjel, anbragt som Correction til 
1 Det vilde til det Øjemed, hvortil saadanne Observationer 
her ere benyttede, nemlig Beregning af Trykket i Dybet, saavelsom 
til klimatologiske Øjemed, være bedre at tage Vandprøverne fra et 
Dyb af 1 å 2 Meter. 
* Zweite Deutsche Nordpolfahrt, II, 7. 
tungen. Bearbeitet von C. Borgen! S. 667. 
Aråometerbeobach- 
gravity of sea-water at ao I have applied precisely as 
the sea-temperatures for the construction of maps showing 
its distribution at the surface and the bottom, as also for 
vertical transverse sections. These represent together the 
distribution of specific gravity, or the proportionate amount 
of salt found in a horizontal or vertical direction through- 
out the North Ocean. During the progress of this work 
various discrepancies made their appearance, that had to 
be eliminated, and for which I shall account. 
Off the coast of Norway, from Stad to Lofoten, the 
direct observations set forth in Tornge’s Map exhibit at 
the surface very sinuous lines for an equal proportion of 
salt. These I have seen fit to equalize, and have drawn 
my lines along the coast (Pl. XXXIV) without giving 
them any considerable curvature. The determinations of 
specific gravity at the surface have been made with water 
taken from the surface itself. Here, divers causes, such as 
precipitation, rapid evaporation, may easily occasion local and 
temporary deviations from the normal proportion of salt. 
In 1877 and 1878, the amount of salt was determined 
both by the areometer and by the amount of chlorine. 
As will appear from Tornge’s Tables, the results of the 
two methods exhibit as a rule very satisfactory agreement. 
In such eases, I took the mean of both, after first converting, 
according to Tornge’s mode of procedure, the figures in his 
Column: — Amount of Salt by the Amount of Chlorine to 
å TOS «ds : 
Spec. Gravity at =e In some cases, the deviation is 
rather considerable between the areometer and the chlorine 
determinations. By means of the maps and the transverse 
sections, I could see at a glance which of the determina- 
tions agreed best with the system based on the other ob- 
servations; and this was chosen, to the exclusion of the 
other, whether a chlorine or an areometer-determination. 
Since it was of interest the system should be 
extended to different parts of the North Ocean which 
our Expedition had no opportunity of traversing, I sought 
to supply the deficiency by means of observations from 
other Expeditions. First in this respect stands the second 
German Arctic Expedition.” Since the areometer-obser- 
vations from various Expeditions — at least the earlier — 
will not admit of comparison unless the instruments made 
use of — which was not the case with ours — had been 
directly compared; and as it can easily happen that the system 
resulting from one year’s observations may be somewhat dif- 
ferent to that from another year’s — which indeed would seem 
to have occurred in the present case — I instituted a direct 
comparison between the German observations from the surface 
and the Norwegian for the tract extending from the North 
1 For the purpose to which such observations are here applied, 
viz., computing the pressure in the deep, as also for certain climatologi- 
cal studies, it would be better to take the;samples of water from a 
depth of one or two metres beneath the surface. 
2 Zweite Deutsche Nordpolfahrt, IL, 7. Aråometerbeobach- 
tungen. Bearbeitet von OC. Borgen. Page 667. i 
LAS 
