10 



(a) Lower trace shows build-iqj of wave at the 22-ft station. 



(b) Upper trace shows build-up of wave at the 38-ft station. 



(c) Steady-state conditions at both measurement stations. 



Figure 6 - Record of Wave in the 140- ft Basin 



Photographic copy of one continuous record taken in the 140-ft towing basin. The upper trace on each 

 strip shows the record obtained from a gage placed 38 ft from the wavemaker; the lower trace shows the 

 record obtained from another gage placed 22 ft from the wavemaker. 



Since October 1952, both of these measurement systems have been in continual use on one 

 or another of the various research programs currently being conducted at the Model Basin. 

 It is felt that this instrumentation, although simple in principle and design, represents a 

 forward step in the technique of recording small wave heights and wave forms. 



