FOREWORD 



This developmental report describes the methods, results, and 

 conclusions from the first year's data obtained from a cooperative 

 program between the U. S. Navy Hydrographic Office and the Mine 

 Hunting Unit (now a part of the Harbor Defense Unit) at Norfolk, 

 Virginia. Additional reports will follow describing the second year's 

 data and a second test site. 



J^Q..\> 



H. C. DANIEL 

 Rear Admiral, U. S. 

 Hydrographer 



Navy 



