MINSENER SAND 



BORKUMRIFF 



WESER 



AUSSENJADE 



24 25 26 27 28 



TIME (JANUARY 1937) 



29 



30 



FIGURE 14. COMPARISON OF WAVE HEIGHTS OBSERVED ON DIFFERENT LIGHTSHiPS 



INI THE NORTH SEA 

 (SEE MAP, FIG. 13 ) 



19 



