82 GEOLOGICAL POSITIONS. 



systems of Geology than the mere laws of nature, to which all pheno- 

 mena are generally referred ; and the science is thus placed upon a new, 

 a more solid, and more consistent foundation *. 



SECOND LINE OF ARGUMENT. 



1. A river consists of the fresh waters of a district, seeking their 

 level in the waters of the ocean. 



2. Rivers usually flow in valleys to which their own size and force 

 bear no sort of proportion, and which must, therefore, have been 

 formed by an agency distinct from that of the waters now flowing 

 through them. 



3. These valleys must have been scooped out by a force, similar to 

 that of which we have distinct proof in the valleys of the chalk districts, 

 which have never been occupied by rivers. We are also certain of this 

 having been an aqueous agent, from the well known fact of their always 

 ending on the exact level of the ocean. 



4. All valleys occupied by rivers terminate at length in this general 

 level, in the same manner as the chalk valleys, without rivers, once 

 did, though these latter are now often cut short by sea cliffs. 



5. The bed of every river is a plane, more or less inclined, according 

 to circumstances. 



6. As we know that the corroding action of the sea is incessant, and 

 consequently that all sea coasts have been gradually encroaching on the 

 lands, from the very first moment that they became sea coasts ; as we 

 also know with certainty, that, at the period when this action first 

 began, the valleys must all have terminated, as they still do, in the 

 exact level of the sea ; we have a right to conclude that the time cannot 

 be very distant when this corroding action first began. 



7. If we assume that the general average decay of a coast is but one 

 foot per annum (and it will not be denied that it is considerably more 

 upon a large proportion of coasts) ; and if we take so short a period, 

 (geologically speaking) as only one hundred thousand years, we must 

 suppose that more than eighteen miles have been lost, from the original 

 mouths of all rivers. 



8. Had this been the case, we must have found a waterfall, or rapid, 



* A detail of the facts on which the above positions are founded, has been sent 

 to the editors of the London and Edinburgh Philosophical Magazine and Journal, 

 in which work they will probably soon appear, in the form of two papers. 



