DESICCATION AS A PHASE OF THE GLACIAL EPOCH. 189 



Avater as resultiiio- from its sudden meltinsr, has not taken as firm hold of 

 them as it has on investigators in tlie same branch of science in tliis country. 

 The reason why this is so will, as the writer believes, be understood without 

 difficulty, after perusal of the following chapter, which has to do especially 

 with glacial phenomena. That to some extent, however, views prevail there 

 in regard to the diminution of moisture on the earth similar to those so gen- 

 erally held ill this country will appear from the following quotations. 



Mr. D. Mackintosh, in his work on the character and origin of the scenery 

 of England and Wales, when discussing the subject of former increased 

 fluviatile action, remarks as follows : " Mr. Prestwich and others, seeing the 

 difficult}^ of explaining the breadth of many vallej'S by existing river-action, 

 have had recourse to the theory that during the breaking up of the glacial 

 conditions which once prevailed in the north-west of Europe, and the melt- 

 ing of ice and snow, the rivers must have acquired a great increase of vol- 

 ume and consequent breadth of excavating power." * 



Mr. James Geikie adopts a similar view, and quotes the opinion of one of 

 the eminent Swiss geologists in regard to the supposed connection of the 

 Sahara with the Glacial epoch, a theor}- to which reference has already been 

 made,t and which will be noticed again farther on, making the following 

 remarks: "It would seem that during a comparatively recent period the 

 desert of Sahara was submerged, recent mai-ine shells having been found 

 widely distributed over its surfoce [this statement has been shown by later 

 researches, with which Mr. Geikie was not acquainted, to be incorrect, the 

 marine deposits in question occupying but a very small portion of the vast 

 area of the Sahara] and imbedded at some depth in the sand. It is highly 

 probable that, as Escher von der Linth has suggested, this submerged con- 

 dition of the Sahara obtained during the Glacial epoch, and that much of the 

 moisture which then fed the great snow-fields of the Alps was brought by 

 the prevalent winds Oowing from Africa across the Sahara Sea and the 

 Mediterranean." t 



What remains to be done, in the present connection, is to show that con- 

 necting the observed phenomena of desiccation, as presented to the reader 

 in the previous chapter, with the epoch of glaciation does not offer a satis- 

 factory solution of the problem before us. How that epoch does connect 



* The Scenery of England and Wales, its Character and Origin : London, 1S69, p. 280. 



t See ante, pp. 146-149. 



J The Great Ice Age and its Relation to the Antiquity of Man. London, 1S74, p. 402. 



