76 



ombord ikke i fjerneste Maade vil kunne gjøre Regning 

 paa at épnaa, hvorhos man "tillige vil have den Fordel at 

 kunne benytte directe Saltbestemmelser som Controlmiddel. 



Mod de paa Expeditionen udførte Luftbéstemmelser 

 vil ikke kunne gjøres nogen væsentlig Indvending, med 

 mindre man skulde anke over. at cle benyttede Yandprover 

 ere optagne ved Hjælp af Apparater, tier ikke vare om- 

 givne med slette Varmeledere, saaledes at de ved An- 

 komsten til Overdåden vikle have havt Anledning til at 

 antage en i Forhold til sin Luftmængde noget for hoi 

 Temperatur. Denne Feilkilde kan dog ikke antages at 

 have faaet nogen væsentlig Indrlydelse i et Hav som det 

 her undersøgte. hvor kun et meget tyndt Lag nærmest 

 Overfladen besidder en Temperatur af over 5". især da 

 Vand, der kun er svagt overmættet med Luft. meget lang- 

 somt giver Sliji paa den overskydende Del. 



Det ved Udkogningen benyttede, af Jacobsen beskrevne 

 Apparat er i alt Vsesentligt fondet særdeles bekvemt, kun 

 vikle det maaske være hensigtsmæssigt at give Luftopsam- 

 lingsroret en noget forandret Form. hvorved man lettelig 

 vikle undgaa den Vanskeligbed, hvormed det nu er for- 

 bundet at overfykle Luftmængden i Eudiometret uden Tab. 



board; moreover. there is the additional advantagé of being 



able to test the results by direct salt-determinations. 



As regards the air-determinations performed on the 

 Expedition. their general accuracy can hardly be impugned. 

 True. the apparatus with which the samples of water were 

 collected not having been surrounded by a non-conducting 

 medium, tliey may possibly in their passage to the surface 

 have assumed a temperature somewhat too high as com- 

 pared with the amount of air contained in them: but the 

 error arising from this source cannot have exerted any 

 material infiuence, since the tract of ocean investigated 

 has but a thin stratum of water in which the temperature 

 rises above 5"; besides. water slightly surcharged with air 

 is found to part very slowly with the surplus portion. 



The boiling-apparatus devised by Jacobsen proved 

 very convenient; possibly. however. the tube for collecting 

 air might be given a somewhat different form. to obviate 

 the difficulty now experienced in transferring the air to 

 the eudiometer without loss. 



Ovenstaaende Afhandlinger ere indsendte til Redac- 

 tionscomiteen for den norske Nordhavsexpeditions Oeneral- 

 beretning. No. I og II i April 1S7'J og No. III i Decem- 

 ber samme Aar. 



De i disse 3 Afhandlinger beskrevne Observationer 

 ere. forsaavidt de ikke ere udførte ombord, anstillede i 

 Professor Waages Afdeling af Universitetets chemiske La- 

 boratorium i Christiania. 



Sluttelig benytter, jeg ^Anledningen til at udtale min 

 Tak til DHrr Professorerne Waage og Mohn for den Bi- 

 stand, de under mit Arbeide med disse Gjenstande paa 

 tiere Puncter har ydet mig. 



These Memoirs were sent in to the Editorial Com- 

 mittee for the Norwegian North- Atlantic Expedition as 

 follows: — Nos. I aud II in April 1879 and No. III in 

 December. 



The observations set forth in the foregoing Memoirs 

 were. when not tåken on board. instituted in Professor 

 AVaage's department of the Chemical Laboratory of the 

 University of Christiania. 



In conclusion. I must not omit to thank Professors 

 Waage and Molm for the assistance they kindly rendered 

 me, in certain respects, when engaged on the investigatip é n 

 of the subjects treated of in these papers. 



E r r a t a. 



Page 3, line. 26, Ironi top of page, for ■:!"•.! to 32.4 — 33.6 per cent, being' read '35.4 to :;■.'. 4, :;:;.<> per cent being.' 



— 0, lino 20, trom top "f page, for 'the extent to which the results based on tlnit hyppothesis,' etc. read 'the slight 



rxt>Mit to which Jacobsen's results.' etc. 

 — 28, line 22, from top ol' naire. for 'soda was aililcd, and the whole compound' read 'carbonate of soda was 

 added, and tin 1 whole misture.' 



— 38, line "'. from foot ol' page, for 'soda' mul ■carhonate of soda.' 



— 'M. line 13, fr foot of page, for 'soda' read 'carbonate of soda.' 



Translated into English by John Hazeland. 



