REPORT 1902-03 APPEND. A _ XLIV — 



tried on the same occasion, by which the current -meter could be anchored at 

 the bottom and so made independent of waves and strong surface currents as 

 well as of the motion of the ship, and this principle has proved successful. It is 

 hoped that after some technical improvements the G. L. will be able to recommend 

 it for use on the regular cruises. 



By request experiments have also been made with a current-meter invented 

 by Prof. 0. Pettersson. In this apparatus the direction of the current is not deter- 

 mined relative to a magnetic needle attached to the current- meter but relative 

 to a long- rod hung by a bifilar suspension from the ship. This principle may be 

 recommended for current measuring at small depths, where a magnetic needle would 

 be influenced by the iron of the ship. 



VII. Gas analysis. 



In 1903 experiments have been made to find a reliable and quick method 

 of determining the gases dissolved in sea water. These experiments are still in 

 progress, but seem to be successful. An especial point of the new apparatus is 

 that it allows of a complete, accurate analysis of oxygen, nitrogen and carbonic 

 acid with only one sample. 



Experiments have also been begun to find a reliable method of sterilising 

 the water samples without influencing the estimation of the gases dissolved. The 

 problem seems to have been simplified and altogether this work has been much 

 facilitated by exhausting the tubes with a Töpler pump instead of by filling them 

 with merrcury as freqently seems to have been done. This method is confi- 

 dently recommended. It is hoped that particulars of these experiments will shortly 

 be available for the use of the international expeditions. 



VIII. The laboratory has had as guests two assistants of Prof. Otto Petters- 

 son who have during a part of January and February made experiments on ocean 

 currents. 



Christiania, ßth August 1903 



Fridtjof Nansen 



