- 30- 



Denis caused by the rain water drainage through the estuary. The 

 latter is a distinguishing feature of the Barataria Bay circula- 

 tion because it is indeed a river mouth of rather peculiar shape. 

 Test A is concerned with a detailed study of rainfall drainage 

 and its effect in tending to exclude the waters of both Lake 

 Grande Ecaille and Bay Ronquille from Barataria Bay proper. In 

 the eastern areas there is known to be an unusual division of the 

 directions of ebb currents in the southern part of the Lake 

 Tfeshington system which causes the flood and ebb currents to di- 

 verge. Ebb currents flow north in part of Lake Washington and 

 south in the region nearer Bay Chaland and reverse on the flood. 

 The position of this division in the model was found to be in 

 good agreement with field observations. Through the expedient 

 of interposing the 20 by 20 mesh screens in the seaward passes the 

 calculated rate of going of the tide machine was made acceptable. 

 The calciilated fresh water discharge through the Little Lake 

 equivalent box led to a correct phase and duration of flood and 

 ebb currents with respect to high and low water at Barataria Pass, 

 Insofar as it is possible to estimate the reliability of a model 

 with respect to field observations, the Barataria Bay model prob- 

 ably possessed a kinematic figure of merit of about 8 on a scale 

 of 10, Since good quality field observations are generally rated 

 at about this same figure of merit, and they alone reveal the 

 behavior of the prototype, the estimated correspondence of the 

 model to the true behavior of the prototype must be between 6 



