1 



Z Hours 



Fig. 7. Experiment 3. Ordinates represent logarithms of numbers of particles 

 not ingested. Since K is not constant the initial K's only can be used in compari- 

 sons. Experimental ratio, 1: 0.35; theoretical ratio, 1: 0.18. Ratio of K from 

 the end of the experiment is 1 : 0.21. The two sizes of quartz particles correspond 

 to the largest and smallest in Figs. 5 and 6. See Table IV. 



Log A-x 



1 Hours 



Fig. 8. Experiment 4. Repetition of Experiment 3. Only the initial i^'s give 

 any basis for comparison. Experimental ratio, 1: 0.38; theoretical ratio, 1 : 0.18. 

 See Table IV. 



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