328 Scepticism in Geology, [June, 
causes now in a&ion, and we seek to ascertain what is going 
on at the present time.” 
I suggest that the difficulties thus described are overcome 
if, to the causes now in aftion, as enumerated by geologists, 
we add that of growth. “ Verifier ” is most successful in 
his criticism when he attacks “ the theory of the erosive 
power of running water, and the conclusion that the valleys, 
gorges, and beds of rivers, many of them composed of the 
hardest and most indestruftible of rocks, in all parts of the 
world, have been cut by the streams now running through 
them, however inconsiderable.” He observes that, “ the 
writers of the modern school of Geology adopt this as the 
basis of cosmical operations. Their system cannot work 
without it ; it is laid down in their elementary manuals, and 
reasoned on in the profoundest of their philosophical papers, 
and those who dare to doubt are treated with ridicule. . . . 
Those who dwell near the rushing waters of cataradls are 
unconscious of the abrasion of a single foot or inch within 
the term of man’s memory. The frequent growth of water- 
plants, mosses, sea-weeds, &c., on the very surface washed 
by rapid currents, ought also to create doubts as to the truth 
of this prevalent notion. Its general acceptance seems to be 
due to the confounding together of certain undoubted fluvi- 
atile operations. . . . Many of the great river-valleys display 
miles of lateral precipice, rising often to heights of 1000 and 
2000 feet above the water, almost invariably as smooth and 
even as the walls of a house. No proof exists of any of the 
processes of watery action above enumerated being able to 
produce straight cliffs, i.e., walls of rock.” He further says 
that, “ the Prussian engineers, at any rate, had no faith in 
such aid in 1833, when they had some trouble in removing, 
by means of gunpowder, the well-known reef stretching 
across the Rhine at Bingen, upon which so many barges had 
suffered wreck during hundreds of years, to the injury and 
opprobrium of Hanseatic commerce. Yet notwithstanding 
the full stream of the Rhine during so many ages had been 
unable to wear away this comparatively slight barrier, we 
are taught by geologists to believe that the long avenue of 
lofty precipices, including the Lurley, a little lower down, 
and consequently the whole of the gorge from Bingen to 
Neuwied, 60 miles long, have been cut through this same 
river Rhine.” 
I may here observe that Lyell does not attach such ex- 
clusive power to the erosion of running water. On the 
contrary, he complains that Hutton and Playfair ascribe 
valleys in general “ too exclusively to the action of rivers 
