718 
Proceedings of the Royal Society 
Report on the Gas Contents of a number of Samples of Sea Water. 
By Professor Dittmar, F.R.S. 
The waters were left at my laboratory by Mr. Murray in the month 
of August. 
In obedience to instructions received they were boiled out, the 
gases collected, measured, and analysed ; care being taken to use the 
same methods as had served for corresponding work done in connec- 
tion with the “ Challenger ” expedition. 
The samples were contained in bottles of about one litre’s capacity, 
provided with well-fitting glass stoppers. The bottles were almost 
full to the top ; the empty air-space amounting to only 7 c.c. or 
thereabouts. The samples stood in my laboratory for some weeks 
before I received my orders as to what I should do to them ; but 
they were carefully protected against direct sun-light, or elevation of 
temperature by other causes, and the stoppers never lifted before 
the contents were taken out to be worked up. Hence the dissolved 
gases are not likely to have changed much either qualitatively or 
quantitatively during the storage of the waters; the less so as the 
percentage of oxygen in the gas minus carbonic acid was in all cases 
found to be little different from, what (according to my analyses of 
the “ Challenger ” water-gases) is generally met with in surface 
waters. 
The boiling-out of the gases was effected by means of Jackobsen’s 
apparatus, the flask of which held 740 c.c. of water. The flask in 
each case was charged by means of a long necked wide funnel going 
to the bottom of the flask ; through this funnel water was run in 
until about 100 c.c. of water had run over the edge of the flask. 
This 100 c.c. of water, which was allowed to go to waste, could be 
assumed to’ include all that portion which was, to more than the 
absolutely unavoidable extent, affected by contact with the atmosphere 
of the laboratory. In regard to the rest of the work I may content 
myself with referring to my report on the “ Challenger ” gases. 
Labels . 
I. “ Bottom Water No. 31; 11th August 1880. Depth, 515 
fathoms.” 
