30 BURIAL MOUNDS OF THE NORTHERN SECTIONS. 
to erect such structures. We have here the almost exact circle, save 
where interrupted by the margin of the bluff, the overlapping of the 
ends, and the narrow entrance-way. We have here also the clay with 
which it was the custom, at least in the southern section, to plaster the 
palisades or which was cast against their bases as a means of support 
ing or bracing them at the bottom, a custom not entirely unknown 
among the northern tribes in former times. 
The indications are therefore very strong that this enclosing wall was 
originally a palisade which had been in part plastered with clay, or 
against which clay had been heaped to assist in rendering it firm and 
secure, and, if so, then it is probable it was built by Indians. 
Be this supposition right or wrong the evidence is conclusive that the 
area on which this group is situated has been the abode of at least two 
tribes or peoples: first, it was occupied by the authors of the enclosures, 
whose stay was probably not very protracted, and after they had aban- 
doned the locality or been driven from it by a second tribe, evidently 
comparatively numerous, that made it for along time a dwelling place; 
a tribe differing in customs from its predecessor, and one that did not 
rely upon enclosures for protection. By no other supposition can we 
account for the fact that the refuse layer which covers the interior of 
the circle also spreads in equal depth over the ditch and clay remains 
of the enclosing wall, as those who left this refuse layer could have 
made no possible use of the wall as a defensive work, for which the 
position chosen and other particulars show it was designed. 
The form of this enclosure, as we have before intimated, seems to 
connect it with some one of the Indian tribes; its age is uncertain but 
the accumulation of refuse matter and sand since the abandonment by 
the first occupants indicates considerable antiquity. 
Although we cannot say positively that the second occupants were 
the builders of the mounds, as the investigation was not as thorough as 
it should have been, still I think we may assume, with almost absolute 
certainty, that such was the fact. The mounds in the square work 
marked D, in Plate I, present considerable differences from those in 
the group, and are probably the work of those who built the enclos- 
ures. 
The stone grave in the oblong mound indicates the presence of indi- 
viduals of a more southern tribe! at this place, during its second oceu- 
pancy. The position of the cist in the mound would seem to forbid the 
idea of an intrusive burial, otherwise I should certainly suppose such to 
be the fact. I cannot, in the present paper, enter into a discussion of 
the question ‘to what tribe or people are the box-form stone graves to 
be attributed,” but will state my conviction to be, after a somewhat 
careful study of the question, that they are to be ascribed to the 

