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



declare something concerning the composition of the original rocks ; but this can 

 be found out much better from the finer particles, as their number is always 

 far greater. 



As far as we know, the whole of the coast of Siberia along which the 

 Fram sailed, consists of very quartziferous rocks. On the Western Taimur 

 Peninsula, granite is found, and crystalline schists ; on the Chelyuskin Penin- 

 sula, quartzite has been observed. The coarser-grained rocks were not to be 

 found as such in the bottom-samples, which contain only very small particles; 

 the fine-grained are met with in a few of them, but on account of their minute- 

 ness are always in a rather unrecognisable condition. It is impossible to say 

 whether the quartzite found in samples Nos. 6, 7, and 9 comes from the 

 quartzite in situ on the Chelyuskin Peninsula. There are still such great 

 stretches of the coast that are quite unkown, and moreover the material is 

 quite as likely to have originated from the loose materials on the coast, which, 

 over long distances, have been observed to form plains outside the solid rocks, 

 and, as such, will be more likely to be carried away by the shore-ice and the 

 waves than the solid rocks. As these looser deposits consist largely of mo- 

 rainic formations, and may have their origin in rocks that are in situ at a 

 considerable distance, it would be quite impossible to say anything about the 

 first origin of the by no means many kinds of rock, found in the samples. 



With regard to the concretions of iron that are found in certain of 

 the samples in quite considerable numbers, there may be some doubt about 

 their primary or secondary origin. It has long been a well-known fact 

 that on the floor of the ocean concretionary formations of iron and 

 manganese are often formed. Concretions of iron are of course also found 

 in the rocks on land whence the material of the bottom-samples originates; 

 but it is not probable that they would come thence in quantities so large 

 in proportion to other constituents — especially quartz — found in certain 

 of the samples. In such cases then, we must assume that the greater 

 number are formed on the floor of the ocean itself. This is quite certain, 

 notably in sample No. 14, where the concretions of iron considerably 

 outnumber the grains of quartz. They must then be looked upon as formed 

 outside some very ferruginous mineral grains, that have been very easily de- 

 composable. Their degree of firmness is very varied. They sometimes form 

 well-defined, hard bodies; but most of them are of a considerably looser 



