cubic foot (personal communication, G.W. Callendar, CERC, 4 May 1977]], 

 the data on sand addition are of no quantitative value. However, the 

 weight when calculated for 10-hour intervals and compared with the average 

 for the experiments provides qualitative information on periods of signif- 

 icantly greater or lesser erosion. 



(3) Breakers . The primary source of breaker data was the study 

 of the 35-millimeter slides. Table 3 shows the times during runs when 

 slides were taken of breakers. After 100 hours in experiment 70X-10 and 

 115 hours in experiment 70X-06, the practice of taking a slide of the 

 breaker just before the end of the run was discontinued. Knowing the sta- 

 tion of landmarks on the tank wall, the slides provided sufficient data to 

 determine the position and type of breakers throughout the two experiments, 



(4) Water Temperature . After 38 hours in experiment 70X-1Q and 

 throughout experiment 70X-06, water samples were collected at the bottom 

 and at the water surface near the toe of the profile in the early morning 

 and late afternoon of each test day. 



b. Special Data . Three types of special data were collected, and 

 Table 2 indicates the times at which each type was collected. 



(1) Profile Surveys . After 100 hours in both tests, profiles 

 were surveyed along ranges 0.5 foot apart at Q. 5-foot intervals from 

 station -6.5 to +12.0. At 200 hours in the 10-foot tank, and at 150 and 

 175 hours in the 6-foot tank, the seaward limit of the survey was extended 

 to 19 feet. These seaward distances were chosen to provide dense surveys 

 over the most active part of the profile. 



(2) Sand Samples . In experiment 70X-10, sand samples were col- 

 lected at 200 hours, 10 hours before the termination, along profiles at 

 ranges 1, 3, 5, 7, and 9 at 1-foot intervals from station -6 to 0, at 

 5-foot intervals from station to +25, and at other prominent features 

 along each profile. In experiment 70X-06, sand samples were collected at 

 150 hours, near the end of the experiment, along profiles at ranges 1, 3, 

 and 5 at intervals which varied from 2 to 3 feet from station -6 to +26. 



2. Data Reduction . 



a. Wave Height Variability . All wave height data collected in these 

 two experiments were reduced by the manual method. Twenty percent of the 

 wave records were also reduced by the automated method. 



b. Sediment-Size Distribution Data^ . All samples were analyzed in 

 the CERC Petrology Laboratory using the RSA. Approximately 5 percent of 

 the samples were also analyzed by project personnel using the dry sieve 

 method as a quality control measure. 



c. Breaker Data . Breaker type and position were determined from the 

 slides. Using known positions on the tank walls as references, the sta- 

 tion of the breaking point was estimated. Breaker position versus time 



