THE 



POPULAR SCIENCE 

 MONTHLY. 



DECEMBER, 1869. 



THE DESCENDANTS OF PALAEOLITHIC MAN IN 



AMERICA. 



Br Db. CHARLES C. ABBOTT. 



THE modest, peaceful valley of the Delaware River, from the 

 head of tide-water southward, is as little suggestive of the 

 Arctic Circle, for at least nine months of the year, as do its low 

 and weedy banks in summer suggest the tropics. On the con- 

 trary, every tree, shrub, sedge, beast, bird, or fish that you see 

 above, about, or within it is a feature of a strictly temperate 

 climate. Nevertheless, a dim recollection of more stirring times 

 still clings to it, and the year not unfrequently opens with the 

 river firmly ice-bound. Over its shallows are often piled great 

 masses of up-river ice, borne hither after a storm by the swollen 

 current. Often the broad and shallow channel is effectually 

 closed, and the river becomes, for the time being, a frozen lake. 



But the ice, of late centuries, has not been able to hold its own 

 for any significant length of time. The increasing warmth of the 

 sun, and the south winds with their accompanying rains, soon 

 start the little icebergs oceanward, or melt them when they are 

 securely stranded. Except a few scattered masses along the 

 shady shores, the river, by April, is a quiet, shallow, tide- water 

 stream again. 



No appreciable amount of detritus is now brought from the 

 up-river region by a single winter's accumulation of ice. As the 

 river and its shores are to-day, so they were a century ago per- 

 haps for many; but the winter of our varying year is a mere 

 puppet-show compared with what New Jersey winters once were, 

 and the culmination of arctic rigors gave our Delaware Valley, 

 in that distant day, a far different aspect ; and, with each suc- 



VOL. XXXVI. 10 



