14 



THE DEPOSITS OF THE SEA-BOTTOM. 



Islands, less closely round Iceland, and that they are found in the greatets distance round Greenland; 

 the causes of this are sufficiently manifest, viz. in the first place, that in the small islands a smaller 

 portion of land will correspond to a certain extent of coast, the supply of material from inland conse- 

 quently be smaller, and the erosion of the coast will be almost the only operative factor; in the 

 second place the material carried away from a certain stretch of coast of a smaller island, will be 

 spread over a far greater area of the sea-bottom than that coming from the larger islands, and therefore 

 it will naturally decrease more quickly in thickness. The same phenomenon, of course, may also assert 

 itself by the form of the single lands; thus it is by no means improbable that the circumstance of the 

 curves being closer together round the south point of Greenland than farther up, must be accounted 

 for in a similar way. 



If we now more closely examine the means by which material may be transported from land 

 into the sea, they will be seen to consist in the three following: i) the erosion and transport by the 

 running water; 2) the erosion of the coast; 3) the breaking down of the glaciers, and the subsequent 

 transport of the material by icebergs. Other ways of transport cannot here be taken into considera- 

 tion; for even if volcanic eruptions in connection with the wind, or the latter factor alone, may carry 

 some material into the sea, this material will scarcely in any case be any greater part of the whole 

 mass, and thus it will be of no consequence with regard to the percentage of carbonate of lime. The 

 action of the running water is very unequally distributed within the territory treated of here; while 

 rather large rivers laden with large masses of sediments, are emptying on the northern and southern 

 coasts of Iceland, there are in Greenland only some small streams, and in the Faroe Islands and Jan 

 Mayen they are quite inconsiderable. The effect of the rivers may perhaps be traced at the eastern 

 part of the north coast of Iceland where the amount of carbonate of lime in the specimens is 

 especially inconsiderable, and perhaps also at the southwest coast of Iceland, where the curves in a 

 single place are lying specially far from the land; in the last case, however, other factors must also 

 be acting. The erosion of the coast, on the other hand, acts more equally everywhere, and of course 

 most strongly at the western coasts of the lands; this, however, will not easily occasion a greater 

 deposition of material outside of these coasts, as the currents and the winds will chiefly transport it 

 to the east. Thus the erosion of the coast can upon the whole not be proved to be a factor by the 

 distribution of the deposits, unless the rocks on the shore should consist of essentially other minerals 

 than the inland which is scarcely the case in any of the regions treated of here. As to the transport 

 with ice finally, it of course plays the most prominent part on the coasts of Greenland; large num- 

 bers of icebergs, partly laden with masses of sand, clay, and stones, are constantly carried out into 

 the sea. In what manner this material is distributed on the sea bottom, is dependent on more factors, 

 especially the currents and the temperature; it may be supposed, I think, that the melting icebergs 

 are the cause of the exceedingly small amount of carbonate of lime in the deposits on the west coast 

 of Greenland north of 63 L,at. N. On the east coast the masses of ice are far larger; but on account 

 of their melting to a smaller degree it is to be supposed that the deposit on the sea-bottom is smaller 

 than on the northern part of the west coast, and consequently the amount of carbonic acid in the 

 few stations taken here, is larger than to the west Upon the whole there will always be found that 

 difference between the material carried along by the ice, and that coming with running water or 



