wave action. Some of the tests were repeated with a shorter length of 
tank, to correspond to the prototype tank length for tests involving a 
0.4-millimeter sand. Use of this length will, by comparison with results 
using a previous tank length, permit an evaluation of the comparability 
of tests in the prototype tank with 0.2 and 0.4-millimetér sand where 
different tank lengths were used for each sand. Comparison of the results 
of the tests in the big tank with the two sands of different size was made 
to enable rapid estimates of the greater width of beach fill required for 
smaller grain sands to provide protection equivalent to that for coarser 
sands. Application was necessary for emergency protection following the 
March 1962 Atlantic coast storm. More complete analysis of the data is 
now underway. 
(g) Wave Measurements and Analysis. 
The cooperative visual surf observation program was continued by the 
Research Division of the Board, This program consisted originally of 27 
observation stations distributed along the coasts of the continental 
United States which were operated in cooperation with the U. S. Coast 
Guard. Visual observations of surf characteristics are made at 4-hour 
intervals by the Coast Guard and sent to the Beach Erosion Board weekly. 
The program was initiated in 1954 and has operated continuously since, 
although the number of stations has varied from time to time. 
The instrumented wave gaging program was also continued and wave 
gage records were taken as continuously as possible at all field gage 
locations by the Board, The wave gage at Atlantic City, destroyed in the 
March 1962 storm, was reinstalled. The primary installation was the normal 
BEB relay-type step resistance gage, but several other gages were in- 
stalled to afford comparison. Comparison is being made of pen-and-ink 
records, and also by spectral analysis of records obtained on magnetic 
tape. Of particular interest will be comparison of spectrum analyses for 
a pressure type gage installed near the sea bottom with those of the sur- 
face type step resistance gage. 
A programming device has been developed and installed with certain 
reservoir gages. It permits continuous sampling of the waves, and when 
specific pre-set height is increased, the recorder is turned on for a 
pre-set duration. Sampling continues after this recording, but the re- 
corder will not be turned on unless a second pre-set height is measured. 
If after a pre-set duration the sampled height has not reached this value, 
the recorder will be turned on if the height exceeds the first pre-set 
height. Any number of such height settings can be incorporated in the 
Programmer to enable recording of all desired waves, but eliminate re- 
cording during periods of no interest. 
A 45-foot gage has been installed on the Coast Guard tower at 
Buzzards Bay. This gage is of particular interest in that it may record 
either over the bottom 15 feet of the gage with recording plugs spaced 
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