( 568 ) 



Van Roosendaal and Wind took from the whole of observations 

 made at station H 2 the most probable values direction and velocity 

 of current at the various depths and represented them graphically. They 

 constructed for the different series of observations, each lasting 12 or 

 24 hours, in the first place central vector-diagrams, by drawing from 

 a fixed point the successively determined currents as radii- vectores and 

 connecting the terminal points by means of straight lines or of a curve, and 

 in the second place progressive vector-diagrams, by drawing the current- 

 vectors, this time interpolated for the successive full hours, one after and 

 attached to the other. In the first kind of diagrams the periodical 

 currents, and in the second the residual currents make themselves 

 most apparent. 



The measurements were continued at the station H2 during all 

 the following seasonal cruises of the "Rijksinstituut", first by Van 

 Roosendaal and afterwards by the naval lieutenant Dalhuisen, who 

 succeeded the former in his detachment. At the more recent measu- 

 rements the current-meter of Ekman was always made use of. 



The following table gives the dates of the series of observations 

 and the number of measurements l ). 



l ) A more detailed description of these observations forms the contents of the 

 last issue of the ''Publications de circonstance" No. 36. 



