HYDROGRAPHY. Ilr 



and 89 and close to station 90. Section IX shows that the temperature at the bottom is considerably lower 

 north than south of the last-named ridge, while the same circumstance does not apply to the salinity- 

 In station 96 situated north of the ridge, the temperature at the bottom 735 fathoms (1384 metres) 

 is i°2, at a depth of 600 fathoms (1130 metres) 4% This great difference of temperature is the conse- 

 quence of the Irminger Current not coming in contact with the bottom, after it has passed the ridge. 

 As the cold bottom-water at station 96, proportionally is in possession of a rather high salinity (35-1 1), 

 it becomes very heavy. It may be supposed that there is a recess at the bottom of the sea at this 

 place, in which once cold heavy water has accumulated, and in which it remains whithout being 



frequently renewed. 



SECTION X. 



From station 8 (off Faxe bay) towards Angniagsalik. 



The isohaline 35-25 goes from the surface down to the bottom. Leaving apart the coast-water, 

 which is lying within the said isohaline, the water of the greatest salinity is found in the eastern part 

 of the Denmark Strait, the cause of which is, that the rotation of the earth has the effect 

 of forcing the Irminger Current over in the direction of Iceland. 



When on the basis of the observed temperatures and salinities, we try to draw any conclusions in 

 the following concerning the motion of the water, we shall consider the isohaline 35'25 as the boundary 

 of the Irminger Current. It is a matter of course that we cannot with certainty regard an isohaline 

 as the boundary of a current, and by no means such a special and arbitrarily chosen one as the 35-25 

 isohaline. If for all that the choice has fallen on this one, then it is only due to the accidental posi- 

 tion of the sections; if these had been lying more northerly or southerly, it might perhaps have been 

 to greater advantage to choose another isohaline, and by which very likely the same result had been 

 attained. When thus an isohaline (or isotherm) is used as a line of demarcation for a current, this only 

 means that the real line of demarcation is tolerably parallel with the respective isohaline (or isotherm), 

 so that this line does not indicate the breadth of the current We cannot say for inst, on the basis 

 of the measurings in section X, that the breadth of the Irminger Current is equal to the distance be- 

 tween Iceland and station 9. 



In the middle part of section X, the salinity from the surface to the bottom is less than 35-25. 

 West of this and separated from Greenland by the well known East Greenland Polarcurrent , water is 

 to be found whose salinity exceeds 35-25. Only two measurings, namely from station 12 at the surface, 

 and at a depth of 200 fathoms (377 metres) give this result, and we might perhaps be disposed not to 

 believe in this unexpected state of matters, if not other measurings from the same part of the sea 

 exactly had led to the same result Thus the salinity at station 12 at a depth af 300 fathoms (565 metres) 

 is 35-20, and at 500 fathoms (942 metres) 35-19; at station 13 at a depth of 100 fathoms (188 metres) 

 35-23, and at the bottom 35-24. 



The isohaline 35-25 cannot be drawn with exactness in the western part of the section, on 

 account of the observations being too few. But that it is to be there, may be taken for granted; so 

 that whether it is to be drawn as in the section, right down to the bottom, or in another way, is rather 

 indifferent. The same applies, but in a far greater measure, to the 35-00 isohaline. The principal thing 



