measured in the experiments of Galvin and Eagleson. In some of the eight 

 studies additional information was obtamed, and this is discussed in the 

 description of each investigation given in paragraph 4. 



In the tables, laboratory data are listed first, followed by field 

 data, each in chronological order. The compilation of data in the tables 

 is reasonably complete, but other published studies may exist, especially 

 in foreign literature. Other unpublished data are known to exist (Johnson, 

 1953, and Harrison and Krumbejn, 1964), and field data obtained at Nags 

 Head, North Carolina, by the Coastal Studies Institute of Louisiana State 

 University (Sonu and McCloy, 1966). 



The first column of the table is an identification number (ID) con- 

 sisting of the initials of the investigators (as PMT), the letter L or F 

 to indicate laboratory or field studies, and a number identifying the 

 observation within the particular set of data. The last column of the 

 table, labeled COUNT, is an identification number running from I to 352. 



3. Difficulties in Measuring 



Wave direction (THETAB) is the variable most difficult to measure 

 with necessary accuracy. Visual field estimates are probably least re- 

 liable (Galvin and Savage, 1966) and even vertical photographs must have 

 accurate horizontal control. The possibility of relative error increases 

 markedly as THETAB decreases. 



Longshore current velocity measurements (VMEAS) are more reliable than 

 angle measurements, but this variable must be measured carefully because 

 of the unsteadiness typical of field examples (Putnam, Munk, and Traylor, 

 1949) and the non-uniformity typical of laboratory examples (Brebner and 

 Kamphuis, 1963; Galvin and Eagleson, 1965). 



Wave height at breaking (HB) can be measured with reasonable accuracy, 

 but care must be taken that measured values are representative. The wave 

 gage must be fixed offshore of the mean breaking point and those waves 

 which break before reaching the gage must be eliminated from the averages. 

 Other problems arise because waves in nature have a finite crest length 

 and are almost always subject to refraction effects; and on laboratory 

 beaches, reflection causes partial standing waves which locally distort 

 wave heights. 



Wave period and beach slope can be measured within desirable accuracy 

 under laboratory conditions. Under favorable conditions, wave period can 

 be measured reasonably consistently in the field, either from oscillographs 

 of the water surface or by visual observation. Wei I -control led sounding 

 from a pier permits accurate measurement of beach shape from which a slope 

 may be defined. Similar sounding is necessary for laboratory sand beaches. 



4. Descriptions of Investigations 



The following paragraphs describe the peculiarities of each 

 set of data, in the order that they are listed in the tables, based on 



