1915-16.] The Size of the Particles in Deep-sea Deposits. 219 
XIII. — On the Size of the Particles in Deep-sea Deposits. By 
Dr Sven Oden, Uppsala. Communicated by The General 
Secretary. 
(MS. received December 13, 1915 ; lost by fire May 15, 1916. Second copy received 
July 1916. Read January 24, 1916.) 
CONTENTS. 
1 . 
Introduction .... 
PAGE 
219 
4. Mathematical Analysis of the 
PAGE 
2. 
Theoretical Discussion . 
220 
Accumulation-Curves . 
227 
3. 
Experimental Arrangements . 
. 224 
5. Discussion of the Results 
230 
6. Summary .... 
234 
I. Introduction. 
The sediments which carpet the floor of the ocean have hitherto chiefly 
been subject only to biological and chemical investigations, undertaken 
either in order to determine the character of their organic residues or to 
ascertain their chemical composition. Very few authors have investigated 
the mechanical constitution of deep-sea deposits, i.e. the numbers and 
dimensions of their particles, and the few papers dealing with that subject 
which have hitherto been published are based on measurements of only 
very few groups of particles. 
By means of Schone’s “ elutriation method ” 0. B. B^gghild * has sepa- 
rated four groups of particles of the following diameters: >0 - 5 mm. ; 0 - 5 to 
0 05 mm. ; 0 05 to O02 mm. ; <0*02 mm., from the deposits collected by the 
Danish Ingolf-Expedition and has measured their amount. J. Thouletf has 
made some of the Atlantic deposits collected by S.A.S. the Prince of 
Monaco subject to a mechanical analysis by means of a set of sieves. 
Evidently the results of a similar separation process with subsequent weigh- 
ing of the different fractions can only give a very incomplete idea of the 
real composition of a deposit, unless the number of fractions isolated is very 
large, which again would require a great deal of labour. In his well-known 
* Den danske Ingolf- Expedition, Bd. i, 3, Havbundens aflagringer af 0. B. B^ggliild, 
S. 18-24, Kj^benhavn, 1899. 
f Resultats des campagnes scientifiques , etc., par Albert I, fasc. xix, “Etude des fonds rnarins, 
etc.,” par J. Thoulet, Monaco, 1901. See also J. Tlioulet, “Analyse mecanique des sols sous- 
marines,” Annales des Mines, avril 1900. 
