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Figure 10. — Effect of the addition of extract of a mixture of 

 crude oil and ceurbonized sand on the rate of water filtration 

 of oysters, A mixture of carbonized sand and 200 ml. of crude 

 oil in four liters of sea water were shaken for six hours and a 

 portion of the extract diluted with an equal volume of sea 

 water for the test. Carmine cone method. Arrow indicates 

 time of addition. Plotting as in figures 3 and 4. 



