73 



lidet luftholdige, medens de. der have absorberel sin Luffc- 

 mængde i de arktiske Egne, maa indeholde meget større 

 Mængder, og man vil derfor netop i de paa Expeditionen 

 udibrte Qasanalyser have et fortrinligt Middel til at con- 

 trollere den forken opstillede Hypothese, ifølge hvilken en- 

 kelte Regioner af det iskolde Dyb skulde være opfyldt af 

 Vandmasser, der ialfald delvis havde atlantisk Oprindelse. 

 Foråt viseUdfaldet af en saadan Control har jeg teg- 

 net Kartet No. III. hvorpaa efter samme Princip som det 

 ved Tegning af Kartet No. II befulgte flndes afsat de i 

 Dybet fundne Kvælstofmængder udtrykte i CC. pr. Litre 

 reducerede til U" og 760""" Tryk. ligesom der ogsaa ved Si- 

 den af disse Tal tindes opført den Temperatur, hvorved 

 Søvandet absorberer denne Kvælstofmængde, beregnet til 

 nærmeste hel Grad efter den af de tidligere bskrevne For- 

 søg udledede Formel 



X- 14.4 — 0.23*. 



Det siger sig selv. at disse Temperaturer ikke kunne 

 gjøre Fordring paa nogen stor Grad af Nøiagtigbed. da en 

 forholdsvis liden Feil i Kvælstofbestemmelsen bevirker en 

 meget stor Feil i den deraf beregnede Temperatur. Der 

 findes saaledes flere Observationer, der give Temperaturen . 

 — 4°. en Temperatur, der mig bekjendt ikke er ohserveret 

 i Havet. Dette vil dog ikke forekomme saa urimeligt, 

 iinar man tager Hensyn til. at Sovand af — 2° ved 780""" 

 Barometerstand absorberer en Kvælstofmængde, der paa 

 det Nærmeste gaar op til. hvad der i Ydertilfældene er 

 fondet. 



Farvelægningen er her foretagen saaledes. at de Strog'. 

 hvor Kvælstofmæugden er lunden at være 14.4 CC. eller 

 derover, ere betegnede med blaa Farve, de Strog. hvor 

 Kvælstofmængden ligger mellem 14.4 og 12.5 CC. med en 

 svag rod Farve, medens et mindre Parti, hvor Kvælstof- 

 mængden er fonden at ligge under 12.5. CC, er betegnet 

 med en noget kraftigere rod Farve. Betydningen af disse 

 Farver bliver ligesom i Kartet No. II den. at de rode Far- 

 ver hedække de Str.ækninger. hvor Våndet i mere eller 

 mindre Grad besidder atlantisk Karakter, medens den blaa 

 Farve tilhører de Vandmasser, der have absorberet sin 

 Kvælstofmfengde ved en Temperatur af under 0°, og som 

 altsaa nærmest synes at hidrøre fra de arktiske Egne. 



Ved at sammenligne Kartene No. II og III vil man 

 strax se. at Farvelægningen i disse i alt Væsentligt viser 

 en særdeles stor Overensstemmelse, som paa mange Puncter 

 endog nærmer sig til Congruents, om man end ved nær- 

 mere Betragtning vil linde, at disse Ligheder ikke gaa 

 igjen i alle Detailler. hvad man heller ikke paa nogen 

 Maade kunde vente. Grændserne bliver nemlig paa Kartet 

 No. III paa Grand af < )bservationernes Faatallighed meget 

 vanskelige at bestemme, ja der findes endog her paa om- 

 kring den 65de Breddegrad et større Strøg, hvorom man 

 intet med Bestemthed kan slutte, da der under Analysen 

 tabtes en mindre Del af de Luftprøver. der vare bestemte 

 til at udfylde dette Hul. saaledes at den samlede Luft- 

 mængde desværre ikke kunde maales. Desuden ere ogsaa 

 Observationsfeilene baade for Salt- og Kvælstofbestemmel- 



Den norske Nordhavsexpedition. Tornae: Cliemi. 



with that absorbed in the Arctic regions, wherefore the 

 analyses of gas performed on the Expedition furnish an 

 excellent means of testing the value oi' the hypothesis ac- 

 cording to which certain sections of the cold area are 

 assumed to be made up of water part of which at least 

 would seem to be of Atlantic origin. 



To show the result of such a test. I have anuexed a 

 third Plate (drawn on the same principle as Pl. II). in 

 which are given the different amounts of nitrogen present 

 in deep water, expressed in c.centim. per litre. reduced to 

 0° and a pressure ol'7(><)""". Along with these figures will 

 be found, too. the temperature at which sea-water absorbs 

 such an amount of nitrogen, computed. in whole degrees, 

 by means of the formula deduced from the observations pre- 

 viously described. viz: — 



X- 14.4 — 0.2'åt. 



These temperatures cannot of course pretend to an v 

 high degree of accuracy. a comparatively small error in a 

 nitrogen-determination involving a very considerable error 

 in the temperature. Tims. for instance, several of the ob- 

 servations indicate — 4°. a temperature which, so far as 

 I am aware. was not anywhere observed in the sea, This. 

 however. will not appear so strange, if regard be bad to 

 the fact. that sea-water of — 2°. at a pressure correspond- 

 ing to 780 mm , absorbs an amount of nitrogen which agrees 

 very closely with the highest found on the Expedition. 



The sections in this Plate are coloured as follows: 

 those in which the amount of nitrogen was found to equal 

 or to exceed 14.4 ". blue; those in which it ranged from 14.4 

 to 12.5". light red: a somewhat deeper red serves to indi- 

 cate a small tract in which the amount of nitrogen did 

 not reach 12.5. Moreover. as in Plate II. the red colour 

 indicates water more or less distinguished by Atlantic 

 characteristics: the blue, water in which the nitrogen was 

 absorbed at a temperature below 0°, and which. therefore. 

 would seem to have derived its origin from some part of 

 the Polar Seas. 



A comparison of Plates II and III will at once 

 show considerable agreement in the distribution of colour, 

 many of the sections almost coinciding; though. on doser 

 inspection this approach to congruity is not found to char- 

 acterise all details. which indeed there was no reason to 

 expect. In Pl. III. the limits proved exceedingly difiicult 

 to denne, owing to the limited number of observations; 

 nav. respecting an extensive tract near the lioth parallel 

 of latitude nothing defmite can be inferred. part of several 

 samples of air. the analysis of which would have served 

 to lill up the blank, having heen unfortunately lost. and 

 the total amount of air could not. therefore. be measured. 

 Besides. the errors of observation both in the salt and the 

 nitrogen determinations. are so considerable. when com- 

 pared with the minute differences in amount. that. in some 



11 



