Meddelelser om Grønland . aratus and the bulb B. The manipulations aremade in the following order (see fig. 4). The gas-burette €? is filled with mercury. 343 The tube ? is connected with ? and placed so that theconnection at d can be made in an instant. Then the bulb ? is connected with the bottle, care beingtaken first to fill the space above the tap a with water fromthe bulb. The tap a is now-opened and the drops ofwater which have, duringthe shaking, found theirway into the tube ? areforced out through thetail-boring of the corre-sponding tap by openingit for a moment. Thereupon the prin-c
Meddelelser om Grønland . aratus and the bulb B. The manipulations aremade in the following order (see fig. 4). The gas-burette €? is filled with mercury. 343 The tube ? is connected with ? and placed so that theconnection at d can be made in an instant. Then the bulb ? is connected with the bottle, care beingtaken first to fill the space above the tap a with water fromthe bulb. The tap a is now-opened and the drops ofwater which have, duringthe shaking, found theirway into the tube ? areforced out through thetail-boring of the corre-sponding tap by openingit for a moment. Thereupon the prin-cipal boring of ? is opened,and the connection at dquickly performed. Themercury in the burette eis lowered and the sampledrawn in. If everything is cor-rectly performed there will be at the finish a slight excess of pressure in the burette, thecontents of which are therefore for a moment put into communi-cation with the atmosphere by means of the tail-boring of ?before the tap f of the burette is finally Fig. 4. The analysis of the air-sample. As the amount of carbonicacid to be determined is always very small and often less ^lo of the sample it is obvious that the utmost care mustbe bestowed upon the analyses. As already mentioned, I used, during my journey in Green-land, a HALDANE-apparatus by means of which oxygen as well 344 as carbonic acid could be determined with an accuracy of per cent., respectively. This degree of accuracy wassufficient for my purposes at the time, and I think that it willsuffice for some time to come for determinations of COg-tension in freshwaters. Generally, however, it will be of nouse to be able to determine the percentage of oxygen, and Iwould therefore recommend the apparatus specially designedby Haldane for the estimation of carbonic acid in air 4. Itsconstruction is very simple, the manipulations are easy whenno greater accuracy than /0 is wanted, and the apparatusis of very small compass (8 X 13 X 3 i
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectgeology, booksubjects
