1915- ^O. 2. SPITSBERGEN WATERS. IO5 



of these titrations, and thus we cannot arrive at any certainty on this 

 point. 



Otherwise the lowest amounts of oxygen found by our observations 

 were 6.79 cc. at Stat. 14 in Cross Bay, at 250 metres 11.35° C-- 34-84° 00). 

 6.93 cc. at Stat. 37 at 200 metres (1.71*^0., 34.88 "^ 00) ' ^^.r north of Spits- 

 bergen, and 6.96 cc. in the deep-water at Stat. 57 at 700 metres, besides 

 6.75 cc. in the warm water of the Atlantic Current at Stat. 56, at 100 

 metres 1447'^ C, 35.02 o^). 



It seems a striking feature that the most north-eastern station is the 

 one that gives, on the whole, the lowest amounts of oxygen (6.99 cc. at 

 50 metres, and 6.93 cc. at 200 metres). The explanation may possibly 

 be that the water of these layers, examined at this station, has not for a 

 long time been near the surface, which is covered by lighter water, and 

 during a great part of the year also by ice. The water has probably 

 come from the west and south, it may to some extent be intermixed with 

 the warmer water of the Atlantic Current, and its oxygen may gradually 

 have been reduced by the action of animal plankton and by oxidation due 

 to the decomposition of sinking dead plankton. 



Some Observations of the Hydrogen Ion Concentration 

 in the Northern Sea-Water. 



During the cruise with the X'eslemöy in 19 12, a number of measure- 

 ments of the Hydrogen Ion concentration were also made at different 

 stations by the colorimetric method of Sørensen and Palitzsch [see 

 Palitzsch, 191 1]. In most cases a-naphtolphtalein was used as indicator, 

 giving blue reactions. When the value of the hydrogen ion exponent pa 

 was above 8.07. phenolphtalein was also used as indicator, giving red 

 reaction. 



The results of the observations are given in Table I\'. The values 

 of the hydrogen ion exponent, pn, given in the 4th column, were found 

 in the manner described by Mr. S. Palitzsch, and have been corrected for 

 what he calls "the salt error'". 



As Mr. Gaarder has suggested, and Mr. Palitzsch has accepted, it would, 

 however, be preferable in Oceanography to introduce, as expression for 

 the reaction of the sea-water, not the value of pn but the value of the 

 concentration of hydroxyl ions, that increases with the alkalinity of the 

 sea-water. 



