1915-16.] The Size of the Particles in Deep-sea Deposits. 227 
a certain “ accumulation-curve ” characteristic of each sample ; and a 
mathematical analysis, which I shall now briefly describe, allows us to 
Fig. 2. 
transform this accumulation-curve into a “ distribution-curve,” i.e. a 
graphical representation of the statistical composition of the sample. 
IV. Mathematical Analysis of the Accumulation-Curves. 
Thanks to the method described in the preceding paragraphs, we are 
now able to construct a new type of curve, the “ accumulation-curve,” 
