174 V. WALFRID EKMAN. 



it is possible that these may also give valuable hints for future 

 current-observations. Finally, before going on to give an account 

 of these observations, I desire to acknowledge with warm gratitude 

 the kind and active interest with which Prof. Nansen has all 

 through followed my work. 



Lysaker Fjord and the situation of the observation-stations 

 upon it are shown in the sketch-map, PI. XVII, the numbers of 

 the stations being given in Roman numerals, I to VI. The fjord, 

 as will appear from the map, is a fairly open bay of the Chris- 

 tiania Fjord, and its depth increases regularly towards the mouth, 

 passing imperceptibly into that of the main fjord. The latter, 

 on account of the regular steamer traffic, was free from ice; and 

 the edge of the ice extended, during the period from about the 

 10th to the 15th April, nearly from Huk to Rolsfluene, as shown 

 on the map. At the head of the little bay at Lysaker, a small 

 river empties itself, which, however, during the time that the ob- 

 servations were going on, delivered very little water. From this 

 river out to the edge of the ice ran the line of stations, mea- 

 suring about 2"5 kilometres in length, the situation of the stations 

 being approximately determined by pacing. 



With regard to the working out of the observations, I have, 

 for the sake of simplicity, started from a common zero for the 

 sliding weight for all the observations, with an assumed salinity 

 of 30 %o. As will appear from the diagram of salinity, PI. XVIII, 

 fig. 4, this is correct to within 3^/oo everywhere except nearest 

 the ice; and as the currents there were generally rather strong, 

 the approximation made is not injurious to the results. 



I have represented these graphically in diagrams (PI. XVIII — 

 XXII) which cannot be difficult to understand. 



They consist of a round dial, graduated with the magnetic 

 north, east, south, and west, and with concentric circles, the latter 

 here representing the current-velocities 1, % 3. etc. cm. per sec. 

 On this dial the various current-observations are represented with 

 small circles, which must be imagined to be the points of current- 



