152 THE POPULAR SCIENCE MONTHLY. 



these higher points were occupied, the present streams main- 

 tained a uniform flow as high as the freshet stage of these water- 

 courses ; and the fact that an Indian village site near by will be 

 much nearer the river or creek shows clearly, I hold, that on a 

 small scale the same conditions were repeated that occurred in 

 the gradual change from glacial to post-glacial times. The vol- 

 ume of water in all our streams, comparing century with century, 

 is gradually lessening. 



Comparing then the rude objects of argillite, specialized as they 

 are, with the magnificent flint-work of the historic Indians, I 

 would designate the former as fossil implements, the latter as 

 relics. 



To this point I feel that I have been handling facts only, and 

 deducing from them only logical inferences ; but now looms up 

 the natural and ever-interesting question, Who were these people ? 

 The origin of any race is a difficult problem to solve, but none 

 can compare with these misty vestiges of prehistoric humanity. 

 It seems to me but one inference is permissible : they who fash- 

 ioned these rude argillite implements were the descendants of pa- 

 laeolithic man, and his superior in so far as a knowledge of the bow 

 and arrow and rude pottery indicates. Beyond this, perhaps, we 

 can not safely venture. Prof. Haynes has recently observed, " The 

 palaeolithic man of the river gravels at Trenton and his argillite- 

 using posterity the writer believes to be completely extinct." 

 While this at present seems to be the generally accepted conclu- 

 sion, there is a phase of the subject that merits consideration. 

 May not this " argillite-using " man have been a blood-relation of 

 existing Eskimos ? To accept the view of Prof. Haynes that " ar- 

 gillite " man became extinct infers an interval of indefinite length, 

 when man did not exist on our central Atlantic seaboard ; but if 

 we may judge from the abundant traces of man that have been 

 left and of the relation as to position that these three general 

 forms, palaeolithic, later argillite, and Indian, bear to each other, 

 it would appear that, in the valley of the Delaware, at least, man 

 has not for a day ceased to occupy the land since the first of his 

 kind stood upon the shores of that beautiful river. 



By referring these intermediate people to the existing Eskimos, 

 I would not be understood as maintaining that these boreal people 

 were directly descended from the argillite-using folk of the Dela- 

 ware Valley, but that both were derived from palaeolithic man ; in 

 other words, that with the disappearance of glacial conditions in 

 the Delaware valley, and the retirement northward of the continen- 

 tal ice-sheet, if such there were, the people of that distant day fol- 

 lowed in its tracks, and lived the same life their ancestors had 

 lived when northern New Jersey was as bleak as is Greenland to- 

 day ; but that not all of this strange people were so enamored of 



