MAN AND THE GLACIAL PERIOD. 



629 



locality afterward. But neither of us was ever so fortunate 

 as to find a palaeolithic implement in place, or even in the 

 fresh talus of the bluff facing the river. As our experience 

 is that of many others who have visited the locality, and 

 hence of attempts in some quarters to throw doubts upon the 

 genuineness of Dr. Abbott's discoveries, it is worth while to 

 record that Professors Dawkins and Haynes independently 



Fig. 162.— Chipped pebble— black chert, found by Dr. C. C. Abbott, 1876, near the site 

 of Lutheran church, Trenton, New Jersey, in gravel six feet below the surface, a, 

 face view ; b, side view. (No. 10,986.) (Putnam.) 



found implements in the talus over which we had passed a 

 moment or two before ; but, as the attention of Professor 

 Lewis and myself was directed chiefly to the geological prob- 

 lems relating to the character and age of the deposit itself, 

 our failure to discover implements where trained eyes saw 

 them but illustrates the limitations of observers. To distin- 

 guish a roughly flaked human implement in a bed of gravel 

 and pebbles where the ratio of artificial flakes to the natural 

 forms is as one to a million, is like finding a needle in a hay- 

 mow. Hence negative evidence, or a failure of particular 



