8o FRIDTJOF NANSEN. M.-N. Kl. 



the measurements the average current was directed toward S35°W with 

 9.2 cm. per second; but the latter measurements were especially very 

 imperfect. 



At Stat. 20, at 50 metres the measurements gave also an average cur- 

 rent that differed much from that of the chart (Fig. 67). At Stat. 41 there 

 is better agreement between the chart and measurements, and at 100 metres 

 there is also good agreement. 



The shapes of the curves in the region of Stat. 16, west of Cross 

 Bay, are naturally quite hypothetical, as we do not know what the vertical 

 distribution of density may have been over the edge of the shelf Just east of 

 Stat. 16. It is possible that in our section, Fig. 12, through Stats. 15 and 

 16, the layers may have been much depressed over the slope from the 

 edge of the shelf to Stat. 16, indicating a rapid current along this slope 

 (as indicated in our charts Figs. 65 to 68); but in that case the isotherms, 

 isohalines, and isopycnals ought to have been drawn accordingly in Fig. 12. 



Vertical Oscillations of the Water Strata. 



At Stations 19, 20, and 41 a number of vertical series of observa- 

 tions were taken at different times, showing that, especially at the depths 

 between the surface and 100 or 150 metres, there were considerable changes 

 in the water strata at the same station, both as to temperature and salinity, 

 often in comparatively short intervals of time. E. g. at 50 metres, at 

 Stat. 19, comparatively high temperatures, of o. 75*^0., were sometimes ob- 

 served, and at other times temperatures as low as — i. 48^0. and — 1.51'^C. 

 In these cases, however, the salinities also differed so much that the den- 

 city was very nearly the same, about 27.71, and thus the observed changes 

 could not be due to vertical oscillations of strata with different densities, 

 but were rather due to horizontal movements by which heterogeneous 

 waters, of approximately the same density, came into our vertical series 

 of observations. 



In other cases appreciable differences in the densities of the water 

 occurred at the same depths, and the changes were evidently more or less 

 due to vertical oscillations of the water strata, lifting the same stratum 

 sometimes to higher levels than at other times. 



On previous occasions it was pointed out that great vertical oscilla- 

 tions of the strata may probably occur at intermediate depths in the sea 

 [cf. Nansen, 1902, pp. 346 et seq.. Helland-Hansen and Nansen 1909, 

 pp. 89 et seq?\. 



