Date of the Glacial and the Upper Miocene Period. 373 



three scratches, upon a soft sandstone rock, which he could 

 reasonably attribute to floating ice, ought to have aroused the 

 suspicion of the advocates of the iceberg theory that they had 

 really formed too extravagant notions regarding the potency of 

 floating ice as a striating agent. 



There is no reason to believe that the grooves and markings 

 noticed by M. Weibye and others on the Scandinavian coast 

 and other parts of northern Europe were made by icebergs. 

 Mr. Geikie has clearly shown, from the character and direction 

 of the markings, that they are the production of land-ice*. 

 If the rloating ice of the St. Lawrence and the icebergs of 

 Labrador are unable to striate and groove the rocks, it is not 

 likely that those o( northern Europe will be able to do so. 



It will not do for the advocates of the iceberg theory to as- 

 sume, as they have hitherto done, that, as a matter of course, 

 the sea-bottom is being striated and grooved by means of ice- 

 bergs. They must prove that. They must either show that, 

 as a matter of fact, icebergs are actually efficient agents in stria- 

 ting the sea-bottom, or prove from mechanical principles that 

 they must be so. The question must be settled either by obser- 

 vation or by reason ; mere opinion will not do. 



The transporting of boulders and rubbish, and not the grind- 

 ing and striating of rocks, is evidently the proper function of 

 the iceberg. But even in this respect I fear too much has been 

 attributed to it. 



In reading the details of voyages in the Arctic regions one 

 cannot help feeling surprised how seldom reference is made to 

 stones and rubbish being seen on icebergs. Arctic voyagers, 

 like other people when they are alluding to the geological effects 

 of icebergs, speak of enormous quantities of stones being trans- 

 ported by them ; but in reading the details of their voyages, 

 the impression conveyed is that icebergs with stones and blocks 

 of rock upon them are the exceptions. The greater portion of 

 the narratives of voyages in Arctic regions consists of interesting 

 and detailed accounts of the voyagers' adventures among the 

 ice. The general appearance of the icebergs, their shape, their 

 size, their height, their colour are all noticed ; but rarely is 

 mention made of stones being seen. That the greater number 

 of icebergs have no stones or rubbish on them is borne out by 

 the positive evidence of geologists who have had opportunities of 

 seeing icebergs. 



Mr. Campbell says : — " It is remarkable that up to this time 

 we have only seen a few doubtful stones on bergs which we 

 have passed. . . . Though no bergs with stones on them or in them 



* Proceedings of the Royal Society of Edinburgh, Session 1S65— 66, 

 page 537. 



