80 Some Considerations on the Mound Builders. 



is a long intrenchment, not wholly obliterated. At reg- 

 ular intervals, the tracing of this intrenchment projects 

 to the front, so as to make flank defenses, or rudiment- 

 ary bastions, eighty yards apart. On the edge of the 

 town, on the river bluff", is another group of mounds. 

 This group of mounds is inclosed on the side away from 

 the river by a double line of intrenchment, each like the 

 one just described. One of the mounds, eight feet high, 

 stands on a slope. In constructing it three trenches 

 were first dug in the surface of the ground, and then 

 arched over with tempered clay, making three furnaces. 

 Rows of upright sticks or logs appear then to have been 

 placed between these furnaces, partly for the purpose of 

 protecting them from too great pressure. The mound 

 was then made by throwing on earth. But flues of tem- 

 pered clay were made, some extending directly up to 

 the upper surface of the mound, others sinuously wind- 

 ing through it, so as to convey heat to every part. Logs 

 of green wood were interspersed thickly through the 

 mound and bits of dry wood placed about them. When 

 the mound was opened all the wood was found reduced 

 to charcoal, and the whole mound baked almost to 

 brick. In another of the group were found fragments 

 of burned clay flues and bits of charcoal. The first has 

 the appearance of an elaborately constructed charcoal 

 pit, from which the charcoal has not been removed ; the 

 other, one from which the charcoal had been taken. A 

 tree, growing on one of the mounds, was found to be 

 two hundred and fifteen years old. The other mounds 

 were found to contain some bits of pottery and a few 

 stone implements. While these last are undoubtedly 

 works of the natives, it is not easy to believe that the in- 



