ABSTRACT 



Visual wave observations will always be needed to supplement instru- 

 mental records. Ordinary visual observations are not adequate for 

 estimation of the spectral components of the short-crested surface 

 waves, but by the use of more precise visual observations utilizing 

 all the waves passing a point, it is possible to determine the wave 

 characteristics. 

 The most important observed wave characteristic is wave height. The 



theory of a wave rprr,rH 



between 



shown tl' 



for the 



only wav 



visual ob 



to 100 wi 



be estimc 



Visual ob; 



to interpr 



must be I- 



be estima 



from visue 



ri 1- 



jthe relationship 

 spectrum. It is 

 pe derived both 

 tributions using 

 |es of recorded 

 minimum of 50 

 ?ave height can 



5 more difficult 



ive distribution 



ve length" can 



be estimated 



