2 2 THE POPULAR SCIENCE MONTHLY. 



mention a few instances. In 1715 a flint knife, now in the British 

 Museum, was found imbedded in gravel with the tooth of an ex- 

 tinct species of elephant, near Gray's Inn Lane, London, thus 

 marking the extreme antiquity of flint instruments. In 1797 flint 

 hatchets were found in Suffolk, and in 1847 flint instruments at 

 Abbeville. In 1858 Sir Charles Lyell found others in the valley 

 of Somme in Picardy. Flint instruments have been found in 

 caves all over the earth, mixed with bones of animals that lived 

 before, during, and after the Glacial period. They can be more 

 or less classified according to their form and finish.* We believe 

 that in all instances flint instruments have been found with what 

 are supposed to be the earliest skeletons of mankind ; moreover, 

 the oldest type of flint instrument has been found with the skele- 

 ton of man.f 



The difficulty now is to assign a period to the earliest type of 

 flint instrument. If this can be done, the period in which man 

 first appeared on the earth can be more precisely ascertained, and 

 this in two ways either by finding these flint instruments be- 

 neath certain strata which can be assigned to certain periods by 

 geologists, or by finding them with the bones of certain animals 

 the period of whose extinction is also approximately known. 

 This only is certain : that the bones of extinct species of animals, 

 extinct yet still represented by later races, have been found in 

 these and other caverns with those of man and with flint instru- 

 ments. These bones are those of mammalia of the Miocene, Plio- 

 cene, and Pleistocene periods. Secondly, the caverns in which 

 these human bones have often been found have, we believe, been 

 always in the Secondary and Lower Cretaceous rocks, though this 

 does not, of course, show that man was in existence immediately 

 after the formation of these rocks, but merely that they were the 

 most accessible and convenient for him in which to live or be 

 buried, for many of the skeletons that have been discovered seem 

 to have been carefully buried by others. The alluvial deposits, 

 formed by the action of water, which actually contain man's 

 remains, belong to a more modern era than the newest stage of 

 the Tertiary epoch and are within the Post-tertiary series, in the 

 Pleistocene, Glacial, or Bowlderdrift period, as it is variously 



* M. Bonfils, curator of the Mentone Museum, in order to prove how rapidly these flint 

 knives, hatchets, spearheads, daggers, fishing weights, etc., could be made, has himself 

 made many with the aid of only stones with which to commence, and later on with the help 

 of the instruments thus formed. And thus he has found that they only took from five hours 

 to nine days to make, according to the quality of the flint or agate and the form of the in- 

 strument. 



) Previous to flint, man must have used wood, breaking boughs from off the trees and 

 making them into the form of stout staves and clubs, and later into that of wooden spears, 

 bows, and arrows, of which perishable materials naturally no traces can be found. 



