1880.J NATURAL SCIENCES OF PHILADELPHIA. 30t 



that Dr. Abbott had found implements below the surface. Beyond 

 the terrace of older gravels the pala^oliths sometimes occur with 

 implements of the modern tj'pe, but are not imbedded at any 

 depth. In Pennsylvania, moreover, the writer has found similar 

 pahieoliths in the region covered by the Trenton gravel and in that 

 region onh'. Here, then, is the strongest probability, even if the 

 implements were found upon the surface only, that they belonged 

 to and were of coeval deposition with the river gravel. 



The implements of argillite found at the lowest depth in undis- 

 turbed gravel have been generally decided by archa-ologists to be 

 of human origin. It is, however, true that there are many sharp 

 fragments of this rock in the Trenton gravel which are of natural 

 origin, and that pebbles and partially rounded fragments of the 

 same rock are frequent. The writer has found several fragments 

 of argillite in the gravel exposed at the cut near Wheatsheaf 

 Station, Bucks Co., Pa., which, whether they were artificial or 

 natural, it was impossible to determine. 



All the evidence that has been gathered points to the conclu- 

 sion that at the time of the Trenton gravel flood, man in a rude 

 state lived upon the banks of the ancient Delaware. He may have 

 been in the habit of spearing fish and seals with spears pointed by 

 his rough stone implements, and these having been dropped into 

 the flood may have sunk into the loose and shifting gravel. The 

 weathering upon the implements is so slight as to afford no evi- 

 dence of their high antiquity. Many of the paljeoliths found in 

 the river gravels of Europe, are of very similar tjqie. As a rule, 

 probably the implements of the Trenton gravel are somewhat more 

 rude. The writer is informed that even more primitive forms are 

 now in constant use among some of our Western Indian tribes. 



It is interesting to find, as pointed out by archaeologists, that 

 until lately the Eskimos have used stone implements quite as rude 

 and similar in appearance to those found in the Trenton and other 

 river gravels, and it has been suggested that that race, now living 

 in a climate and under conditions perhaps similar to those once 

 existing on the Delaware, may have some kinship with the pre- 

 Indian people of this river. It ma}' be that an Eskimo race, living 

 here at the time of the flooded Delaware, were driven north by 

 the coming of the Red Indians. If future archaeological work 

 shows this surmise to be correct, the writer suggests that the 

 period of the Trenton gravel and of this palaeolithic people, — a period 



