Fig. 28.—Cross section of Fort Deposit Cave at 30 feet.[ToList]
At 38 feet the yellow earth had risen until it was within 3 feet of the top of the entire overlying deposit. The latter contained little of the dark earth, being mostly composed of ashes and burned earth, some of which resulted from fires made on the spot, but the greater part being thrown from other points. The rise of the yellow earth, consequently, is more rapid than the rise of the material covering it.
Fig. 29.—Cross section of Fort Deposit Cave at 35½ feet.[ToList]
At 40 feet there was a dip in the yellow earth, extending for 4 or 5 feet and descending 2 feet at the deepest point. This may be due to drainage at a lower level.
At 47½ feet a pocket of the dark earth extended a few inches into the underlying yellow earth. A hole seems to have been dug into the latter. There was no more of foreign material in this hole than elsewhere in the dark earth above and around it. It is shown in figure 30.
Fig. 30.—Cross section of Fort Deposit Cave at 47½ feet.[ToList]