22 0. B. B0GGILD. BOTTOM DEPOSITS. [norw. pol. exp. 



region has scarcely been raised above the sea in the Quaternary Period, nor 

 probably in the Tertiary either. 



As the particles of more than 0"5 mm. appear in such exceedingly small 

 quantities, it follows that the sandy particles on the whole must be consider- 

 ably in the minority as compared with the clayey particles. In the case of 

 the 4 samples of Grey Deep-Sea Clay, the average quantity of particles between 

 0'05 and 0*5 mm. is 6 - 03 per cent, while in the Ingolf Expedition it is 29 - 55 

 per cent — quite a striking difference. An increase in the quantity of the 

 finest particles will of course be found in the Fram samples in a correspond- 

 ing degree. 



A number of quite important variations between the several samples, also 

 appear in the details. In order to obtain a better idea of these, and to give 

 as clear a picture as possible of the mechanical composition of the samples, 

 I have tried to represent this graphically, and have given the size of the 

 grains as abscissa and the percentage as ordinate. In practice, however, 

 this presents certain difficulties, and it becomes necessary to discuss more 

 fully the manner in which a representation such as this, may be made. 



The marking of the figures on the ordinate presents no difficulty what- 

 ever. The percentages may be put down in an ordinary arithmetical series, 

 which will prove to be sufficient in all cases. This is by no means the case 

 with the abscissa figures. If we attempt in a similar manner to put down 

 the figures denoting the size of the particles in an arithmetical series, it will 

 be impossible in the great majority of cases to find a scale which will include 

 all the sizes of the particles in the sample, and at the same time give a cha- 

 racteristic representation of the most important constituents of it. This may 

 be best illustrated by one particular example. Sample No. 1 contains, as we 

 have seen, 0"22 per cent of particles of more than 1 mm.; the largest is 1"55 

 mm. If all the sizes of grain are to be included in one scale, this may be 

 divided, for instance, into 30 parts of 0'05 mm. each. The particles of more 

 than 1 mm. will extend over 10 divisions, and will thus average a height of 

 0'022, which it will be impossible to] show on a drawing unless the units of 

 the abscissa are very large, and this, as we shall presently see cannot be 

 done with the finer particles. The particles of sizes between 05 and 1 mm. 

 also extend over 10 divisions. As they are found to the amount of 1*21 °/o, 

 the curve will here be drawn at a height averaging 0*121 units, which at any 



