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and a steady state escists, an appreciable thickness of the surface 

 water will be moving at a speed in the order of 2 to 3 per cent 

 of the steady wind speed. In the Barataria Bay model the average 

 steady wind speeds in each of the cardinal and intercardinal direc- 

 tions were computed from data si^plied by the Grand Isle station 

 of the U. S. Vileather Bureau, The blowers were driven at the proper 

 rate to produce a Vj, scaled surface water motion equivalent to 

 2.5 per cent of the average wind speed wherever the fetch vra.s 

 great enough in each case. Every precaution was taken during the 

 wind calibration and the model tests to have the model surface 

 scrupulously clean so that the surface tension of the water skin 

 maintained a uniform value and the rigidity of the skin was as 

 low as possible* Before each test the surface was cleaned first 

 by an ionic detergent and thereafter by a scummer. Tests were 

 not begun until the detergent had had time to hydrolize and dif- 

 fuse into the volumes of water below the surface. Since the ac- 

 tion of the surface active agent is essentially monomolecular in 

 thickness the resulting volume contamination was truly negligible. 



The average wind velocities were calculated from statistics 

 for the year 1946 prepared by the New Orleans Office, U. S, 

 Weather Bureau, from observations made at Grand Isle, Louisiana, 

 and are as follows: 



