J 98 On the basaltic Surface of the Counties 



sea ; a resemblance I cannot trace in any country which I 

 have observed, nor could our sudden and perpendicular ab- 

 ruptions ever have been produced by any agitation of the 

 waters. 



Professor Playfair considers rivers as having formed not 

 only the. beds or channels in which they flow, but also the 

 whole of the valleys through which they run, and in gene- 

 ral all the inequalities of our surface; but an attentive ob- 

 server, tracing the course of any of our most rapid rivers, 

 would soon perceive that the quantity of its depredations 

 have been comparatively insignificant, and that they can be 

 determined with precision : the river has no doubt in several 

 places extended itself considerably on both sides, but in the 

 intermediate space between the remotest boundaries it ever 

 reached, it levels, instead of raising inequalities. 



The same result I apprehend would follow from the ope- 

 rations of another agent, which theorists are in the habit of 

 calling in to their aid, when they cannot find some certain 

 material, which from their theory we had reason to expect ; 

 they then tell us it has been carried off, and lost in the suite 

 of degradations and decompositions. 



But decay and decomposition, instead of creating inequa- 

 lities, would produce a contrary effect, and deface those ac- 

 tually existing; they would gradually abate the height of our 

 perpendicular facades, and increase the green steep at their 

 bases by the accumulation of the crumbling and mouldering 

 materials from above ; while the more diminutive facades 

 formed by the abruptions of single strata scattered over the 

 face of our area, and forming its most characteristic feature, 

 would in time (as many are already) be converted into steep 

 acclivities covered with verdure. 



Such are the principal causes to which the inequalities of 

 our surface have been generally ascribed. Previous to our 

 deciding finally upon their insufficiency, it may be proper to 

 enumerate a few of those inequalities, where the deviation 

 of our present surface, from the form it probably had origi- 

 nally, is not only striking, but where also the concomitant 

 circumstances afford demonstration, that some great opera- 

 lion has once taken place there, 



Thus 4 



