312 LECTURE XI. 



to serve as handles, some were longitudinally split for the sake 

 of the marrow. Similar characters have been obsei-ved in the 

 kitchen-middenSj as well as in the bones of the Swiss pile 

 works. 



Desnoyers's discovery was confirmed by leading men in sci- 

 ence. It is true that MMj Robert and Bayle objected (evidently 

 to save the theory of Beaumont) that the scratches on the bones 

 in the collection of the Ecole des Mines of Paris had been made 

 by the preparer of the specimens, who scratched ofi" the ad- 

 hering sand with a chisel. Desnoyers found, however, no dif- 

 ficulty in proving that the objection was puerile, for four 

 reasons : because the bones not in the Ecole des Mines have all 

 the same striee ; because the bones taken directly from the 

 sand-pit also have them ; because in these notches there are 

 sandgrains, and therefore the bones must have been thus 

 marked before they were imbedded ; and, finally, because the 

 said white sand adheres so little to the bones, that no chisel, 

 but only a little water, is required to cleanse the bones. 



As, however, Desnoyers's discoveries must as yet be consi- 

 dered as isolated, we are still justified in asserting that, gene- 

 rally speaking, man has only appeared in Europe and North 

 America during the so-called diluvial, post-pliocene, or quater- 

 nary period. 



There is ample evidence, that this last period was accom- 

 panied with a considerable refrigeration of our hemisphere, 

 which increased so much that at a certain period the whole of 

 Switzerland, the Scottish Highlands, Scandinavia, and a por- 

 tion of North America were covered with ice. The question 

 now arises : Did man exist in France, Belgium, and England 

 before or after this glacial period ? The question is so far in- 

 teresting, that in case of man's pre-existence the glacial period 

 may have put a stop to his existence in the aforesaid regions. 

 But let us examine the geological conditions apart from man. 



Everywhere in Scandinavia, North America, and England, 

 as well as in the vicinity of the Alps, we meet with a formation 

 which is generally called glacial-loam or boulder-clay. This 

 formation, of marl or plastic clay, which in all countries is used 

 in brickmaking, is spread over the surfaces in layers of varying 



