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organisms and organic matter. The "deep-water" of the Central Basin has a 

 relative contents of oxygen of roughly, between 80 and 40 "/o decreasing 

 gradually inwards. 



Taken as a whole, the movement in the lower stratum and in the 

 "deep water" is everywhere directed inwards; in the Central Basin towards 

 east and north, in the Gulf of Finland towards the East, and in the Gulf of 

 Bothnia towards north. The momentary direction of current is, however, 

 greatly dependent upon accidental factors, and must be regarded as very 

 variable. During an inflow of very salt water, by which the water of the 

 hollows was renewed, the bottom current between Arkona and the Dantzig 

 Deep has been found to move at an average speed of at least 3 nautical miles 

 in 24 hours, or 6 cm/sec. 



The totality of the current in the upper stratum is directed towards 

 the mouth of the Baltic, the resulting movement of upper stratum water 

 however, describes, from the beginning of the summer to some way on in 

 winter, a circular movement, against the clock, in the Central Basin and the 

 northern Gulfs: i. e. inwards along the eastern and southern coasts, the resul- 

 tant amounting in spring to some few cm/sec, later up to 10 cm/sec. Local 

 conditions are here of considerable influence. 



The tidal phenomenon is slightly pronounced, but has been thoroughly 

 investigated and is highly interesting. 



