28 F. L. Ekman, 



has there to pass over bars, which have, at the most, 10 to 13 fathoms 

 (18 ... 23 mètres) of water over them. Between the Danish Islands and 

 the Skagerack the depth increases on the whole pretty uniformly to 

 about 30 fathoms (54 mètres), though at places depths of 50 fathoms (89 

 met.) have been found. But in the Skagerack the depth increases very 

 rapidlj^, so that between Jutland and Norway the depth sometimes ex- 

 ceeds 300 fathoms (534 met.) and reaches 100 fathoms (178 mètres) at 

 many places near the Swedish coast. This deep channel, as is known, 

 thence continues along the coast of Norway; its south terminus penetra- 

 tes some distance into the Kattegat with a depth of about 50 fathoms (89 

 metr.). The oceanic under-current has then in this part averj^free approach 

 and the locality is accordingly characterized by uniform saltne.^is in deep 

 water and variable at the surface. At 340 fathoms (606 mètres) I obtai- 

 ned samples of 3.515 7o saltness; at 100 fathoms near the Swedish coast 

 the saltness is 3.50 7o5 ^^^^ ^^ ^*^ fathoms (17.8 met.) I have never found 

 less than 3 "/o- ß^^t at depths less than that the differences of saltness 

 are far greater. The outflowing upper-current, in consequence of east- 

 ward deviation, keeps near the Swedish land, and by its bottom and 

 west side affects the surrounding sea-water, thus producing a reac'tion- 

 stream. The water, that flows in through the Skagerack, does not there- 

 fore go exclusively to compensate, in the form of an under-current, that 

 water, which is carried off" from the Kattegat and the inner basins by 

 the surface-current, but a great part of it proceeds in the form of a 

 stream, that reaches up to the surface, along the Danish coast towards 

 the Swedish coast, to unite itself in the Skagerack with the outflowing 

 stream, which falls into the North-Sea at the southern coast of Norway. 

 Thus, while the saltness on the Jutland-coast approaches that of the 

 North-Sea-water, that on the Swedish coast is only about 2 Va ", o ^^^ sum- 

 mertime; it moreover exhibits great changes at different seasons and 

 under different circumstances, because the causes, which determine the 

 strength of the surface-current and the efflux of the superficial water 

 from the Skagerack, are subject to variation. 



In the Kattegat the saltness of the surface-current is far less than 

 in the Skagerack, because it has not j^et received the above mentioned 

 reaction-stream. In the northern part of the Kattegat the saltness is 

 about 2 7o5 ^"t in the southern parts the percentage sinks considerably 

 below that. The saltness of the under-current is here also less, because 

 it is here obliged to approach nearer to the upper fresher water-strata. 

 Nevertheless the under-current in the south part of the Kattegat and in 



