ii6 Cincinnati Society of Natural History. 



straight. It will be seen, then, that the turns or changes in 

 direction take place at the openings or gate-ways. This 

 arrangement exhibits quite a high degree of engineering 

 skill. By adopting this plan, the sections of wall could be 

 built straight, thus savang much labor. 



The third section of wall, south of the north ravine, and 

 which .stands immediately south of the Chillicothe and 

 Lebanon road, has the greatest elevation, which is twenty-two 

 feet. It has a top-length of seventy-eight feet and a width of 

 base of seventj'-four feet. The angle of slope of sides is 

 about thirty-six degrees. Its summit, though well rounded 

 off, is cjuite massive, so that by a very little leveling down, it 

 would be sufficiently wide to accommodate a standard-gauge 

 railway. In all respects, except in size and length, this sec- 

 tion of wall does not differ materially from the others. 



A person standing some distance to the west, on the inside 

 of the fort, will be surprised at the evenness of the summits 

 of this and the next two much longer sections of embank- 

 ments that extend to the south. And he will be more sur- 

 prised when he notices how closely their tops range with each 

 other, and at the almost exact horizontal line which is thus 

 formed against the eastern sky. The straightness of this line 

 is slightly marred by a downward curve of from eight to ten 

 inches in the top of the section next to the road, caused, 

 doubtless, by water standing at its base on the outside of the 

 fort. This has affected the ground beneath the middle of the 

 wall, causing it to settle. 



This accurate summit-range is the more remarkable, when 

 we consider that these sections of wall vary considerably in 

 height, as measured from the surface of the ground. We 

 must conclude that this accurate top-range was intentional on 

 the part of the builders, and that the reason of its remaining 

 unchanged is owing to the fact that the height of the embank- 

 ments has ])een but very little affected since their construc- 

 tion. If these sections of wall had been carried up to a con- 

 siderable distance above their present elevation, and to quite 

 a narrow ridge, as many suppose, and then worn down by 

 natural agencies to the height we now find them, there would 

 be no such accurate summit-range. The extent of wearing of 

 the different sections would not l)e the same. And it would 



