on the bottom at a point in the transition zone at some depth, H. 
for example as summarized most recently by Snodgrass [1951], are 
for all practical purposes useless. For that matter any step in 
current practices which involves the assumption that the "significant" 
period can be treated as if it were a discrete spectral component 
automatically introduces huge errors for "sea" records which com- 
pletely invalidate all quantitative values which result from the 
analysis. 
In order to demonstrate this point, some statements will be 
quoted from the paper by Snodgrass [1951]. Then the point at which 
the error was made will be shown. Finally Snodgrass' analysis of 
the inaccuracies which result will be interpreted in the light of 
the results shown in this chapter. Selected quotations from the 
paper referred to above follow. 
eens. oie The following basic definitions have been accepted 
(Folsom, 1949): 
Ete Sieerere 
3. Wave period is the time interval between the appearance 
at a fixed point of successive wave crests. 
4. Characteristic wave period is the average period for 
the well-defined series of highest waves observed. 
"Analysis of wave records for wave period. Analysis of 
wave records for the characteristic period is accomplished by 
measuring the average period of the larger, well-defined waves 
appearing on the record........ The characteristic period of 
the waves does not describe the period-distribution, as the 
characteristic height describes wave-height distribution. ..... 
ora op information is needed to adequately describe wave 
periods. 
2D 
