280 LECTURE X. 



Alps) J interposed between molasse strata^ for diluvinnij and lias 

 compared these beds, for wbidi no fossils bave yet been found, 

 to the alluvium of the valleys where elephant bones have been 

 met with. Hence this transposition of the diluvium into another 

 epoch ; hence this repudiation of still acting forces, as regards 

 the above formations, for which he invokes unknown forces, 

 which cannot at present be traced in nature. 



As regards the slopes, there is a small point which must not 

 be forgotten, namely, that the motion of water does not merely 

 depend upon the fall, but also upon the mass, and that a 

 navigable river flows down more rapidly than a small brook, and 

 that rain water remains, to a certain extent, stationary. 



With respect to chemical analysis, it may be said that the 

 amount of organic matter only then furnishes a kind of natural 

 chronometer when the respective bones are found in the same 

 positions. If this be not the case, the chemical analysis has 

 scarcely any importance, as those influences, which deprive the 

 bones of their animal matter, act with greater intensity in one 

 locality than in another. 



The note of Elie de Beaumont, which we have rendered ver- 

 batim, is partly an answer to the communication of Hebert, 

 laid before the academy in May, which I also subjoin. Hebert 

 is intimately acquainted with the environs of Paris, and has, 

 with other geologists, taken part in the Scientific Congress. 



" The celebrated Secretary of the Academy of Sciences," 

 writes Hebert, " ought to have noticed that we were specially 

 occupied in investigating this question ; that we are far from 

 confounding the various accumulations of conglomerates ; that 

 we have shirked no difiiculties ; but that these difiiculties do 

 not invalidate the facts that man has existed in France since 

 the beginning of the quaternary or diluvial period. 



" With regard to the special locality of Moulin- Qui gnon, I 

 have declared at Abbeville, that this conglomerate, consisting 

 partly of broken or entire and frequently large flints, which 

 seem to have come from the subjacent chalk, and are cemented 

 together in a brown firm clay, which here and there contains 

 sandy parts ; I have declared, I say, that this formation does 

 not, in my opinion, belong to the lower diluvium, which occurs 



