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MARINE BOTTOM SAMPLES OF LAST CRUISE OF CARNEQE 



sion in the sea itself. Colloidal particles carried in sus- 

 pension in rivers, however, quickly coagulate into larger 

 grains and settle on coming into contact with sea water. 

 On the other hand, the rate of coagulation must become 

 slower as the process of flocculation continues, since 

 the distance between the particles becomes greater and 

 greater, and a few particles will be carried far from 



shore before settling. A similar conclusion was reached 

 by Murray and Irvine (1891). 



In so far as these pelagic deep-sea sediments con- 

 sist of materials of continental origin, they represent a 

 largely permanent loss of relatively heavy substances 

 from the continent and a corresponding gain by the sea 

 floor. 



