70 
ombord ikke i fjerneste Maude vil kunne gjøre Regning 
paa at opnaa, hvorhos man tillige vil have den Fordel at 
kunne benytte directe Saltbestemmelser som Controlmiddel. 
Mod de ]>aa Expeditionen udførte Luftbestemnielser 
vil ikke kunne gjores nogen væsentlig Indvending. med 
mindre man skulde anke over. at de benyttede A andprøver 
ere optagne ved Hjælp af Apparater, der ikke vare om- 
givne med slette A'armeledere, saaledes at de *ved An- 
komsten til OverHaden vikle have liavt Anledning til at 
antage en i Forhold til sin Luftmæiigde noget for hoi 
Temperatur. Denne Feilkilde kan dog ikke antages at 
have faaet nogen væsentlig Indfiydelse i et Hav som det 
her undersøgte, hvor kuu et meget tyndt Lag nærmest 
OverHaden besidder en Temperatur af over 5°, især da 
Vand. der kun er svagt overmættet med Luft, meget lang- 
somt giver Slip paa den overskydende Del. 
Det ved Udkogningen benyttede, af Jacobsen beskrevne 
Apparat er i alt Yæsentligt fundet særdeles bekvemt, kun 
vilde det maaske være hensigtsmæssigt at give Luftopsam- 
lingsrøret en noget forandret Form. hvorved man lettelig 
vikle undgaa den Vanskelighed, hvormed det nu er for.- 
bundet at overfylde Luftmængden i Eudiometret uden Tab. 
. Ovenstaaende Afhandlinger ere indsendte til Redac- 
tionscomiteen for den norske Nordhavsexpeditions General- 
beretning, No. I og II i April 1879 og No. Ill i Decem- 
ber samme Aar. 
De i disse 3 Afhandlinger beskrevne Observationer 
ere. forsaavidt de ikke eré udførte ombord, anstillede i 
Professor AV aages Aldeling af Universitetets chemiske La- 
boratorium i Christiania. 
Sluttelig benytter jeg Anledningen til at udtale min 
Tak til IVHrr Professoreme AVaage og Mohn for den. Bi- 
stand. de under 'mit Arbeide med disse Gjenstande paa 
flere Puncter har ydet mig. 
board; moreover, there is the additional advantage of being 
able to test the results by direct salt-determinations. 
i 
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, they 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 influence, 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. 
These Memoirs were sent in to the Editorial Com- 
mittee for the Norwegian North- Atlantic Expedition as 
follows: — Nos. I and II in April 1879 and No. Ill in 
December. 
The observations set forth in the foregoing Memoirs 
were, when’ not taken on board, instituted in Professor 
AVaage's department of the Chemical Laboratory of the 
University of Christiania. 
In conclusion. 1 must not omit to thank Professors 
AVaage and Moliu for the assistance they kindly rendered 
me, in certain respects, when engaged on the investigation 
of the subjects treated of in these papers. 
Ertata. 
Pa<*e 3, line 26, from top of page, for ‘3.\4 to 32.4 — 33.6 per cent, being’ read ‘3r>.4 to 32.4, 33.6 per cent being.’ 
- 9, line 20, from ’top of page, for the extent to which the results based on that hyppothesis,' etc. read ‘the slight 
extent to which .Jacobsen’s results.’ etc. 
— 28, line 22, from top of page, for Soda was added, and the whole compound' wad ‘carbonate of soda was 
added, and the whole mixture.’ 
— 38, line 3, from foot of page, for ‘soda’ read ‘carbonate of soda.’ 
— 39, line 13. from foot of page, for ‘soda’ read ’carbonate of soda.' . 
Translated into English by John Hazeland. 
