FOREWORD 



Elasticity is one of the properties of bottom sediments having an 

 important bearing upon resistance to penetration. The measurement of 

 plasticity is not a well-standardized procedure. Although both Atter- 

 berg and Rigidense tests are methods of quantitative measurement, the 

 Rigidense method provides the more rapid analysis. This report describes 

 both methods and compares the relative merits of each. 



: B. COCHRAN 

 Captain, U. S. Navy 

 Fydrographer 



