343 



The tube с is connected with Ъ and placed so that the 

 connection at d can be made in an instant. 



Then the bulb В is connected with the bottle, care being 

 taken first to fill the space above the tap a with water from 

 the bulb. 



The tap a is now- 

 opened and the drops of 

 water which have, during 

 the shaking, found their 

 way into the tube Ь are 

 forced out through the 

 tail-boring of the corre- 

 sponding tap by opening 

 it for a moment. 



Thereupon the prin- 

 cipal boring of Ъ is opened, 

 and the connection at d 

 quickly performed. The 

 mercury in the burette e 

 is lowered and the sample 

 drawn in. 



If everything is cor- 

 rectly performed there will 



be at the finish a slight excess of pressure in the burette, the 

 contents of which are therefore for a moment put into communi- 

 cation with the atmosphere by means of the tail-boring of Ь 

 before the tap f of the burette is finally closed. 



Fig. 4. 



The analysis of the air-sample. As the amount of carbonic 

 acid to be determined is always very small and often less than 

 0.03 ^lo of the sample it is obvious that the utmost care must 

 be 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 



