64 ON THE INTERMENTS OF PRIMITIVE MAN. 



wards been ground to a smooth and often polished sur- 

 face. The former kind has clearly preceded the latter, 

 which belongs to a much later period, when the primitive 

 arts had been advanced. But the researches of M. Bouchet 

 de Perthes and others in the drift and high-lying gravels 

 about St. Acheul and other parts of the north of France 

 led to the discovery of a considerable number of large 

 rudely-chipped flint implements, which are distinct in form 

 from the implements of the barrows. These have been 

 named the drift flints, and some of them had actually 

 been discovered and described in England, although the 

 fact was unnoticed and forgotten, many years ago. At 

 first and for some time it was disputed whether these 

 rude flints had not been produced by natural causes, and 

 not by the hand of man. 



More extended researches revealed the fact that these 

 flints were to be met with in many places in England and 

 in France, where the remains of these very ancient gravels 

 had been washed by rivers that had flowed over them at 

 the most ancient period of time. To give some idea of 

 the lapse of years that must have passed, it may be men- 

 tioned that these drift flints often occur among gravels 

 that are now at least 300 feet above the levels of the 

 present streams. The water has slowly washed for itself 

 a course at least 300 feet in depth through the strata 

 which intervene. Another thing which confirms the vast an- 

 tiquity of these drift gravels, is the discovery in them of 

 the bones of long-extinct animals, such as the mammoth 

 (elephas primigenius,) and hippopotamus. More extended re- 

 searches have revealed the remarkable fact that the river 

 drift flints, whether they are met with in the north of 

 France, where they occur in many different districts, or in the 

 south of England, where they have been collected in dif- 



