u 
Da jeg Vaaren 1 H77 blev opfordret til at .overtage 
disse Arbeider, var der kun givet mig faa Dages Varsel, 
saaat jeg havdc de største Vanskeligheder med- at. *faa ud- 
ført selv de aller uødtørftigste Forberedelser, og naar det 
alligevel lykkedes at ffla.Alt tilfredsstillende ordnet for 
Afreisen, da skyldes dette udelnkkende den Beredvilliglied, 
hvormed Hr. Professor Waage bistod mig blandt Andet o g- 
saa med Indredningen af detcbemiske Laboratorium ombord. 
Det paa Expeditionens første Togt i 187(5 fremher- 
skende ualmindeligt stormfulde Veir gjorde det i boi Grad 
vanskeligt ja næsten ugjørligt at udføre de cbemiske Obser- 
vationer ombord, og det Udbytte, som af Svendsen lijembragtes 
fra første Togt. indskrænkede sig derfor i denne Branclie til 
17 Luftprøver, bvoraf - desuden 3 ved Ulield senere gik tabt. 
Det rolige Veir. som de to sidste Aar begunstigede Expe- 
ditionens Arbeider. tillod mig derimod paa de Togter. hvor- 
med der var* givet mig Anledning til at medfølge, at ind- 
smelte et større Antal, idet der for disse Aars Vedkom- 
mende erholdtes 80 Luftbestemmelser af de bjembragte 
Luftprøver, bvoraf 9 vare. indsmeltede af Hr. Schmelck. 
Naar Udbyttet ikke er blevet støiTe, da bar dette sin ti rund 
i. at talrige Observationer gik tabt nogle faa ved Ulield 
under Analysen men de Heste ved Ulield Under Indsmelt- 
ningen. Saaledes var .der til Brug paa sidste Togt fra 
lvUobler & Solme i Ilmenau sendt mig nogle Luftopsam- 
lingsrør. bvoraf over 75 °/ 0 tiltrods for den omliyggeligste 
Behandling sprang enten under Indsmeltningen eller effcer 
samme, Luftprøverne ere alle analyserede ved det afFranck- 
laiul og Ward 1 augivne Gasanalyseappnrat. saaledes at Kul- • 
syren er fjernet med Kalilud og Surstoffet bestemt ved 
Porbrænding med Vandstof. De 14 førstnævnte Prøver 
ere analyserede af Hr. Svendsen de øvrige 80 af forfat- 
teren. De erholdte Resultater findes sammenstillede i 
•Tabel I, hvortil kan bemærkes følgende: De i Tabellen 
opførto Temperaturangivelser ere mig meddelte af Pro- 
fessor Mcrtin. Ved Angivelse af de Dybder, hvorfra Vand- 
prøverne ere bentede, er ikke taget Hensyn til. at Vnnd- 
benteren først lukker sig effcer circa 7 Favnes Indbivning. 
Ved de med * betegnode 10 Nummere var der. i de til 
Luftprovornes Opbevarelse benyttede Glasror smaa Feil, 
uden at jeg dog bar fundet mig foranlediget til at tilla>gge 
disse mindre Vægt end de Øvrige, da man vel ikke kan 
tamke sig Muligbeden af en Læ kage, uden at den, naar 
Glasrørene i 'Here Maaneder opbevaredes under . en Trvk- 
diflerent§ mellera det ydre og indre Gastryk af circa 300 
til 400""", maatte liaVe øvet en incerkbar Virkning paa deii 
indesluttede Lufts Sammensætning. Jeg kan såa meget 
trøstigere tage dem med i Beregjiingerne. hvor det gjælder 
at opstille de almindelige Slutninger, som de ikke i syn- 
derlig Grad ville bidrage til at forrykke 1'dseendet af de 
endelige Resultater. Alle Gasvolumina findés i Tabellen 
udtrykte i CC. per Litre udkogt Søvand reduceret til 0° og. 
7 60’" m Barometerstand. 
1 Chem. Soc. Jour». *22— :U3. 1809. 
When, in the spring of 1877. I was requested to 
undertake these labours. I had but a few days’ notice, and 
experienced, therefore, very great difficulty in making 
even the most necessary preparations; uor would it indeed 
have been possible to- get everything satisfactorily arranged 
in so short a time but for the readiness with which Pro- 
fessor Waage came forward to assist me; for instance, in 
fitting up the chemical laboratory on board. 
The exceptionally heavy weather on the first cruise 
in 1876, rendered it in the highest degree difficult, nay 
well nigh impracticable, to perform the necessary experi- 
ments on board ; and hence the chemical work done by Svend- 
sen on the first voyage was,' with regard to gas-determina- 
tions. confined to collecting 17 samples of air, 3 of which 
however were subsequently lost. On the two- last cruises of 
the Expedition the weather proved much more favourable, 
and I succeeded in obtaining a larger number of samples 
(9 of them collected by Mr. Schmelck), with which, when 
brought home. 80 air-determinations were performed. A more 
satisfactory result would, however, have been obtained but 
for the loss of numerous samples, some few from accident 
when- analysing the gass, but the great majority by reason 
of the difficulty experienced in sealing. Thus, for instance, 
on the last voyage 75 per cent of the glass tubes for 
collecting air, procured from. Kucbler & Solme in Ilme- 
nau, notwithstanding the greatest care cracked either 
during the sealing-process or after its completion. The 
samples of air were all of them analysed in the apparatus 
described by Francklnnd and Ward, 1 the carbonic acid 
having been absorbed in a lye of potash and the oxygen 
determined by consuming it with hydrogen. The first 14 
samples were analysed by Mr. Svendsen, the remaining 80 
by myself. The results obtained will be found in Table I. 
The -temperatures in the Table were given by Professor 
Molm. When stating the depth's from which the samples 
of water were drawn, regard has not been bad to the fact.' 
that the instrument used for collecting them does not close 
till it has been hauled in about 7 fathoms. The asterisk 
marking 10 of the. determinations signifies that, the glass 
tubes used for preserving these samples of air bad small de- 
fects. To these determinations, however. I have not attached' 
)ess weight than to the others; for it is impossible to con- 
ceive that a leakage, after the glass tubes had been exposed 
for month's together to a difference of pressure amounting 
to 300 mm — 400 mm , viz. that existing between the air inside 
and the atmosphere without, should npt have had an ap- 
preciable effect on the composition of the air they contained. 
Moreover, I hesitate the less to include them as factors 
when seeking to arrive at general conclusions, since 
they cannot to any considerable extent disturb the char- 
acter ot the final results. The volumes are given in 
cubic centimetres per .litre of the sea-water examined, 
reduced to a temperature of 0° and a pressure of 760'” m . 
1 Chem. Soc. Journ v 22, p. ;Ji3; 1S60. 
