— 53 — COUNCIL - MARCH 1920 - REPORT 



Holland. The Chairman gave an account of a vertical self-registering 

 tidal gauge at use in the Zuider Zee which had an accuracy of 5 cm in height of the 

 water level. 



He also described a design of Dr. Schoute to eliminate the error due to the 

 bending of the wire in the .lacobsen Current Meter. 



The meeting expressed the hope that these instruments would be made 

 available at the Bureau. 



Denmark. Prof. Knudsen gave an account of his new photometric method 

 for measuring the absorption of hght by sea water. It was suggested by Prof. D'Arc y 

 Thompson that this account would be of great interest to the members of the Royal 

 Society meeting during the afternoon. A vote of thanks was given to Prof. Knudsen. 



5. Current Measurements. 

 Dr. Jee called attention to the Memorandum circulated to the meeting and 

 to the requirements for future investigations. Se Appendix II, p. 66. 



Mr. Edser gave an account of this statistical study of current measurements 

 and showed curves illustrating the various points of his memorandum. 



The Chairman commented upon the results obtained and agreed that 

 continuous observations were necessary. 



Dr. Jee then formally moved the following resolution: — 



"It is desirable that intensive current measurements lasting at least 

 a full year be carried out with the object of tracing the monthly fluctuations 

 of the resulting current of the Channel into the Flemish Bight and that this 

 investigation be closely associated with meteorological observations." 

 This resolution was approved. 



Prof. Witting brought before the Section a proposal with regard to the public- 

 ation by the Bureau of abstracts of the various scientific papers of interest to the 

 International Council. The consideration of this proposal was deferred to the next 

 sitting. 



The section then adjourned. (Signed) E. C. Jee. 



Joint Meeting of Hydrographical and Plankton Section. 



Third sitting: Friday, 5th March, 1920. 

 Professor M. Knudsen in the Chair. 



All Members present together with Mr. Maurice, Mr. Hutchinson (United States) and the 



Delegates of France. 



The meeting was attended by Mr. Harries as representative of the 

 Meteorological Office and opened by considering the hydrographical contribu- 

 tions of each country for the year 1920 — 21. 



