H. H. Hoicorth—A Great Post-Glacial Flood. 307 



its present general direction, hemmed in between the Java (or rather 

 the northern continuation of the rocks of the Jura) on the south and the 

 lower hills of the Schwartzwald that hounded the river on the north. 

 Its level must then have been higher than now in this part of the 

 channel." He again says further on that, "allowing the Miocene 

 strata of Mainz to have attained a height of 500 feet aboA'e the level 

 of the present plain, there may still have been a fall in the river 

 channel on the surface of the ancient plain of more than 300 feet" 

 between Basel and Bingen, the present fall being 531 feet." 

 He concludes that the present Rhine valley has been excavated by 

 the present Ehine " wandering through the long inclined plain of 

 Miocene rocks between Basel and Bingen, and thus by degrees 

 lowering the surface level through the ordinary processes of watery 

 erosion," and explains in this waj'- the occurrence of the stratified 

 banks of gravel at various levels above those of the more modern river 

 terraces, and also the occurrence of the Loess, which he identifies as 

 " only river mud of a comparatively ancient date, and perhaps of 

 glacial origin," being found at many different levels on the slopes 

 that flank the Ehine valley, from 200 feet above the river between 

 Herholz and Ettenheim down to the level of the Rhine itself at 

 Eltville. " As the river by degrees lowered the level of the plain, 

 it left its finer detritus at these and many other levels." Assuredly 

 this theory is most extraordinary in many respects, and it is not 

 surprising that it has failed to gain acceptance. If the Rhine 

 between Basel and Mainz is not at present an instrmnent of 

 denudation, but the reverse, how can we suppose that, when its 

 fall was little more than one-half what it is now, and its flow 

 correspondingly slight, it should have been so, to the enormous 

 extent of sweeping away several hundred feet of strata and carving 

 out the wide valley through which it flows ? 



Again, if the gravel and Loess, which line its flanks and occur in 

 places down to its very level, were deposited by its waters as river 

 mud, how could the river at the same time have been doing the 

 work of destruction ? 



Again, if this vast mass of Miocene strata was bodily removed 

 by the action of the river, where is the debris ? It is true that the 

 flats of Holland are to a considerable extent delta deposits ; but they 

 are much too small to account for the vast mass of materials that 

 should somewhere be forthcoming. Again, how is it that in these 

 delta deposits in Holland or in the Loess itself we should find 

 nothing pointing to their having been the products of denudation 

 of Miocene strata ? We should assuredly have found abundant 

 evidence of Miocene life in a rolled and bi'oken condition both in 

 the Loess and in the superficial deposits of Holland, if this had been 

 so ; but nowhere is this the case. 



On the other hand, as we claim to have shown in a previous 

 paper, the Loess is in no sense a river deposit. In structure, 

 contents, and disposition its origin is most cleaidy marked as being 

 other than fluviatile, and the suggestion that it is so, could hardly 

 have been made if it had been remembered that the Loess is not 



