10 
I A ar fit 1873 udgik atter fra England en Expedition, | 
Challépgere^peditionen. som i et Tidsruin at 3 Aar skulde 
undersøge hande de æquatøriale og antarktiske b afvande. 
Med denne Expedition fulgte som Cliemiker J. Y. Bu- 
chanan. som besluttede sig til at anvende de pan Pomerania- 
expeditionen benyttede Methoder og Apparater saa godt 
som uden Modifikationer. Resultaterne at hans Under- 
søgelser ere, saavidt jeg ved, endnu ikke offentliggjorte i 
sine Enkelthedgr. medens der dog er gjort nogle foreløbige 
Meddelelser, hvoretter man vjl kunne danne sig -et Be- 
greb om de Slutninger, hvortil haus Observationer ville føre. 
Han finder 1 , at >Surstofmængden i Overfiadevandet 
varierer mel lem 33 og 35 % af den samlede- Surstof- 
Kvælstofmængdø, soaledes at den grørste Mærigde . cr 1'undet 
(baade relativt og ahsolut) i Vandprøver øste i Nærheden 
af den sydlige Polarcirkel og den mindste i Pasatvind- 
egnene. Hvad augaar de under Overfiaden liggende Lag, 
da hav han observeret det nuerkelige Factum, at Surstof- 
procentøn nltager nedover indtil etDyh af 300 Favne, hvor 
den opnaar et Minimum for atter igjen at stige, saaledes 
som det fremgaar af følgende Tabel. 
Dybdo i 
engelske 
FavnO; 
0 
25 | 50 
loo ! 
200 
300 j 400 j 
8 oo 
Der- 
over. 
-{- A 7 _ = l oo 1 
■ 0 % 
33*7 ! 
33-4 32-2 
30.2 
33-4 
n -4 15-5 
22.6 
23-5 
Om den absolute Mængde af de af hans Vandprøver 
udkogte Gasarter findes paa dette Sted Intet, hvorimod 
der senere er bleven offentliggjort følgende Tabel 2 . 
Dybde i 
Pod. 
CC. 
0 
per Litre. 
Midlere 
Tempe- 
ratur 
i °C. 
' '• 
CC. N 
per Litre 
A',. • 
CC. iV per 
Litre destill. 
Vnnd ved 
Temperat. r. 
Bunsen 
AV 
A j — A , _ 
600 
4.24 
• i4-"6 
1 1.26 
n -75 
O.49 
1200 
3-59 
13- 0 
II. 71 
1 1.92 
0.2 I 
1800 
1.67 
6- 9 
13.OO 
. 13-45 
0 - 45 ’ 
2400 
2.41 
5 - i 
J 3.!0 
14.00 
0.90 
4800 
4.06 
2. 6 
13.82 
15.00 
1. 14 
derover. 
— 
i- 5 
r 4-37 
15.40 
1.03 
Hermed er i Korthed gjengivet det Vigtigste af de 
til Dato fremkomne Bidrag til Løsningen af Spørgsmaalet 
om Luften i Søvandet. 
I Yaaren 1876. da man i Norge var beskjæftiget med 
I'drustningen af den Expedition, som var besluttet udsendt 
for i Sommermaanederne * af Aarene 1 87 15 — 77 og 78 at 
‘The Voyage of the •‘Challenger.’ Tin* ‘Atlantic." 2 :>(>(>. 
* Ber. Berl. chcnu Ges. 11 —410. 
In the year 1873, another Expedition was dispatched, 
from England, with H. M. 8. 'Challenger.' its object being 
the investigation, during, a period of 3 years, both of the 
Equatorial and the Antarctic Seas. As chemist to this Expe- 
dition. had been secured the services of J. Y. Buchanan, who 
• resolved to adopt the methods and apparatus employed 
on the •Pomerania' Expedition, almost without’ modifica- 
tion. The results of his labours are not yet. I believe, 
published in detail; preliminary papers have, however, ap- 
peared, from which we can form some general idea of his 
results. 
Buchanan found 1 the proportion of oxygen in surface- 
water to vary between 33 and 35 per cent of the total 
amount of oxygen and nitrogen; it was greatest (both re- 
latively and absolutely) in the samples of water drawn 
near the Antarctic Circle, and smallest in those collected 
within .the region of the trade winds. As regards the pro- 
portion of oxygen in water below the surface,, he ob- 
served the very remarkable fact, that it generally dimiushes 
down to a depth of 300 fathoms, where, a minimum is 
reached, and then begins to increase, as shown by the 
following Table. 
• Depth in 
English 
Fathoms. 
0 
25 
50 
100 
200 
300 
400 
800 
Great- 
er 
Dptlis. 
<> A =*100 
0 p. Ct. 
•33-7 
33-4 
32.2 
30.2 
33-4 
11.4 
15-5 
22.6 
23-5 
With respect to the absolute amounts of the gases 
boiled out of the different samples of watei\ nothing is 
stated in the work alluded to. but the following Table 2 has 
since appeared. 
Depth 
in 
Feet. 
CC. 
0 
per Litre 
Mean 
Tempera- 
ture 
in'C. 
t. 
CC. 
A 7 . 
per Litre 
AY 
CC. # per 1 
Litre dis- 
tilled Water, 
at Temp. t . 
Bunsen 
- v - 
n 3 -n, 
600 
4.24 
"f* 
' O ' 
1 1.26 
11-75 
0.49 
1200 
3-59 
13- 0 
II. 71 
I I.92 
0.2 I 
1800 
1.67 
6. 9 
13-00 
13-45 
o -45 . 
2400 
2.41 
5 - i 
i 3 -io 
14.00 
0.90 
4800 
4.06 
2- 5 
13.82 
15.00 
1. 14 
Greater 
Depths. 
— : 
i- 5 
14-37 
15-40 
1.03 
A brief account has now Jieen .given of what had pre- 
viously been accomplished as regards the solution of the 
problem presented by the air in sea-water. 
In the spring of 1§76. when fitting out the Norwegian 
Expedition, which had for . its object the investigation, 
during the summer months of 1876, 1877. and 1878. of 
1 The Voyage of the. ‘Challenger." The ‘Atlantic.’ 2, p. 300. 
1 Bor. Berl. chein. Ges. 11, p. 410. 
