20 



84, 85 og 87, fjerne sig om mere end 1 Proceut fra det al- 

 mindelige Resultat, medens man af samtlige Observationer 

 kan bestemme en enkelt ( >bservations sandsynlige Afvigelse 

 fra den elter denne Tabel optrukne Curve til + 0.52 °/ , 

 en Afvigelse saa liden. at en ikke ringe Del af den kan 

 skrives paa < Ibservationsfeil. 



De største Uoverensstemmelser optræde talrigst i et 

 Dyb fra 300—600 Favne (54'J — 1U97 Meter) men tindes 

 ogsaa enkeltvis i større Dyb. 



Fra Bunden hidrører i de større Dyb kun to Luft- 

 prøver med væsentlig for bøi Surstofprocent nemlig No. 

 68 og 87. optagne fra to Puncter. som mærkeligt nok 

 begge ligge paa en Linie paralel med og tæt ved Grænd- 

 sen mellem den nordover strygende varme Strøm og den 

 sydover forbi Jan Mayen gaaende Polarstrøm. Bortser 

 man imidlertid fra disse de væsentligste Uoverensstemmelser. 

 som bidrage til at give Curven et om end meget svagt 

 Minimum i 300 -400 Favnes (549—732 Meters) Dyb. vil 

 man i Korthed kunne udtale Regelen for Surstofprocentens 

 Aftagen med Dybet saaledes: Snrstofprocenten er i Over- 

 dåden gjennemsnitlig 35.3 og aftager derpaa forst hur- 

 tigt senere langsommere til lieniuiod 32.5 i 300 Favnes 

 (549 Meters) Dyb, bvorfra den med stigende Dyb holder 

 sig paa det Nærmeste constant. Det kan bemærkes, at af 

 de her undersøgte Vandprover 40 ere øste lige ved Hav- 

 bunden. Man vil imidlertid forgjæves bestræbé sig for at 

 opdage nogen Forskjellighed i Egenskaber mellem disse og 

 de fra ligestore intermediære Dyb optagne. 



Hvor det gjælder at studere Yariationerne af den 

 absolute Luftmængde, maa det synes naturligt som Maal 

 for denne at benytte den opløste Kvælstof, idet den ob- 

 serverede Luftmængde paa Grund af det vedvarende For- 

 brug af Surstof i de dybere liggende Lag bestandig kan 

 forudsættes at være mere eller mindre forskjellig fra den 

 Mængde, som vikle absorberes i Overdåden under directe 

 Paavirkning af Atmosphæren. Kvælstofmængden kan der- 

 inind paa Grund af denne Oasarts stærkt udprægede In- 

 differentisme ligeoverfor andre Legemer uden synderlig Feil 

 antages uafhængig af locale Tilfældigheder. 



Anvendes saaledes Kvælstofmængden som Maal fol- 

 den i Søvandet opløste Luft, viser der sig i Fordelingen 

 Ogsaa lier en udpneget Lovmæssighed. naar undtages. at 

 der i de af Svendsen paa det første Togt udforte Obser- 

 vationer overalt er fundet en mindre Kvadstofmængde, end 

 man efter alle øvrige foreliggende Observationer skulde 

 vente. Bortser man imidlertid fra disse paa første Togt 

 udførte 14 Observationer. vil man se. at alle de Øvrige 

 paa faa Dndtagelser nær meget vel stemme overens med 

 de Tal. man kan beregne eller den ved de ovenciterede 

 Forsøg bestemte Formel 



.V= 14.4 — 0.23*. 



85. and 87 exhibiting a difference of more tban 1 per cent 

 as compared with the general result, whereas the probable 

 deviation of a single observation from the curve drawn 

 according to this Table may be computed at + U.52 per 

 cent, a deviation "so small as to arise. probably. in no 

 slight degree from errors of observation. 



The greatest discrepancies refer chiedy to a depth of 

 300 — 600 fathoms (549 — 1097 metres); now and again, 

 however. they were met with in water obtained from greater 

 depths. 



In only two of the samples of air expelled from 

 bottom-water drawn where the depth was great. did the 

 percentage of oxygen prove much too high, viz. in Nos. 68 

 and 87. the samples of water yielding them having been 

 obtained from two spots which. strange to say, are in a 

 line running parallel and in close proximity to the bound- 

 ary between the warm current flowing north and the cold 

 Arctic current dowing south past the Island of .lan Mayen. 

 Xow. if we exclude from these differences the chief of those 

 that contribute towards giving the curve a very slight 

 but appreciable minimum at a depth of from 300 to 400 

 fathoms (540 — l'å'2 metres), the rule according to which 

 the proportion of oxygen is found to diminish with the 

 depth may be expressed as follows: — The proportion of 

 oxygen. which at the surface is 35.3 per cent. begins at 

 once and continues to diminish, at iirst rapidly and after- 

 wards at a slower rate. till it has reached 32.5 per cent, 

 at the depth of 300 fathoms (549 metres). from whence it 

 keeps almost constant. I will not omit to observe, that of 

 the samples of water examined 40 bad been drawn from 

 the bottom; is was, however. impossible to detect any dif- 

 ference in composition between these and the samples ob- 

 tained from equal intermediate depths. 



Wheu investigating the variation in -the absolute amount 

 of air. .it will obviously be advisable to make use of the 

 nitrogen absorbed, since the quantity of air observed in 

 the deeper strata may. liv reason of the steady consump- 

 tion of oxygen. be assumed to differ more or less from 

 that which would be absorbed at the surface under the 

 direct influence of the atmosphere, whereas nitrogen, from 

 the very slight åffinity evinced by that gas for otherbodies, 

 may. without involving appreciable error. be regarded as 

 proof against the accidents of locality. 



If, therefore. the amount of nitrogen be adopted as 

 the standard of measurement for the air absorbed in sea- 

 water. a marked uniformity will liere. too. be found to cha- 

 racterise the distribution. as determined by the observa- 

 tions described, with the exception however ol' Svendsens. 

 on the tirst voyage, by which the amount of nitrogen was 

 found to be less tlian all subseipiently instituted observations 

 V : i \ ■ > reason to expect. Excluding, tben. the 14 observa- 

 tions from the Iirst voyage. all of the otliers. with but fe w 

 exceptions, agree closely with the tigures which may be 

 found by the formula stated above 



N= 14.4- 0.23 1 



