8 On the S/u'lccs of' LochaOcr. 



in regard to many other points of geology, I may declare, as 

 the last survivor of the old Huttonian school, that I have 

 seen ample reason to call in other agents, besides those em- 

 ployed by that school, to account for them. 



The apparent difficulty of assigning a cause for such a flood 

 as the debacle theory assumed, has probably deterred many 

 from adopting it. But a careful examination of effects, and 

 a patient investigation of their modifications, during the siib- 

 sideuce of such a flood, by the local configui'ation of the land, 

 might satisfy every observing mind that the flood had oc- 

 curred, whatever might have been its cause. "We are satis- 

 fied with many things without pursuing a chain of causation 

 at all. Any one meeting with a stream of cold lava, or a 

 mountain composed of cinders and slags, though unacquaint- 

 ed with volcanic phenomena, concludes at once that heat had 

 dealt with them. So when we meet water-worn masses at 

 great elevations, we are satisfied that water had brought 

 them to their resting-place ; and we do not inquire either for 

 the cause of heat in the one case, or whence the water had 

 come in the other. In reference to our present subject, it is 

 not impossible to assign a cause sufficient to raise a wave vast 

 enough to break over the highest portions of our island. On 

 this subject I read a paper to the Royal Society of Edinburgh, 

 in February 1847 ; but it is unnecessary to enter into the 

 subject at present, fartlier than to state that, from various 

 facts which have presented themselves to their knowledge, 

 several of our most eminent geologists have expressed their 

 conviction that a continent existed in the space now occupied 

 by the Atlantic Ocean, of which the British islands, the Faroe 

 islands, and Iceland are remnants. The sudden sinking of 

 much less than the whole of such a continent, could be shewn 

 to be sufficient to raise a wave of ample dimensions to break 

 and flow over the British Islands, and to extend its influence 

 much farther. Assuming then that such a flood as the de- 

 bacle theory assumes had happened, I will now endeavour 

 to shew why I am of opinion that the shelves of Lochaber 

 are proofs of that theory. 



Assuming what has in reality been proved, that the quar- 

 ter from whence the wave proceeded was as mentioned above, 



