ABSTRACT
It is indeed impossible to observe the many strips of originally continuous freshwater formation which rise from the plain of Limagne in long tabular hills, without being convinced that they owe their preservation from the destruction which has swept away the remainder of the formation, to the capping of basalt which all alike possess., and which by reason of its superior hardness would naturally protect the underlying strata from the rains, frosts, and other meteoric agents, to which the uncovered materials of the marly plain left by the emptying of the lake were permanently exposed. Such a capping on the other hand, would afford very inefficient protection against the denuding force of any violent deluge or general current of waters…. (Scrope, 1827, p. 160)
Again, had the whole excavation effected in the freshwater formation of the Limagne been produced at once, by the debacle mentioned above, or by any diluvial or other violent catastrophe, it is clear that the remnants of the lava currents which had flowed into the freshwater basin before this epoch, would be necessarily all found at one level, or nearly so, corresponding to the average level of the bottom of the lake-basin at that time; while on the other hand, all the
lava streams which have flowed since the debacle or supposed deluge, would be found at another nearly uniform, but much lower level, viz. that of the lowest places of the excavated valley. But, as we have seen, no marked distinction of this sort exists;… They are found at all heights from 1500 to 15 feet above the water channels of the proximate valleys. (Scrope, 1827, p. 161)
…the immense abstraction of matter which has occurred in the freshwater formation of the Limagne was for the most part effected gradually and progressively, and went hand in hand with the occasional flooding of parts of this valley and its tributary ravines by lavas emitted in the eruptive paroxysms of the volcanoes on the neighbouring heights. Even were it allowable to have recourse to vague and hypothetical conjectures, we can conceive no gradual and progressive excavating forces, other than those which are still in operation wherever rains, frosts, floods and atmospheric decomposition act upon the surface of the earth. To these agents then we must refer the effects in question, of which, with an unlimited allowance of time, no one will pronounce them to be incapable. (Scrope, 1827, p. 162)
Charles Lyell reviewed Scrope’s book on Central France and justly called it ‘the most able work which has appeared since Playfair’s Illustrations of the Huttonian Theory’ (Quart. Rev., Vol. 36, p. 437). Soon afterwards Lyell in company with Murchison visited the Auvergne and together they published a paper (On the excavation of valleys’ in which they revealed positive evidence of the quantity of erosive work done by rivers in an area that disclosed no sign of the action of a Flood. It was, as the following quotations show, a clarion blast in favour of the fluvialists.
