Archeological Investigations

by Gerard Fowke

This change occurred in the Milltown Cave a very long time ago. Standing on the débris, several feet within the entrance and beneath a part of the roof now perfectly dry and showing no marks of percolating water, is a stalagmite 31 inches in diameter, which has weathered to a depth of 3 to 4 inches from atmospheric influences alone.

Wyandotte Cave.—So much has been printed concerning this celebrated cavern that no mention need be made of its interior features. The place seems excellently adapted as a habitation for primitive people. It is situated on a hill at whose foot is the bank of Blue River. Five miles away, as the road runs, is the Ohio. The backwater sometimes reaches up the tributary for more than 10 miles. The flint-bearing stratum of the Harrison County aboriginal quarries outcrops a short distance away and appears at several points within the cave. The country is extremely rugged, and good springs occur frequently. Game was formerly abundant in the hills, and Blue River still rewards the angler with various species of fish, many of them of large size.

A former race, presumably the modern Indian, did much work within the cave. Tons of travertine or stalagmite, the so-called alabaster, have been quarried from some of the deposits, while a large number of flint nodules has been dug out of the cave-earth where they fell from the disintegrating limestone. Some of this labor was carried on more than a mile from daylight.

The mouth of the cave was formerly almost closed by a mass of talus. About 10 feet has been removed from the top of this, so that one may now walk in without difficulty. On the inner side of the portion remaining there is a slope for 96 feet, to a vertical depth of a little more than 27 feet. The next 100 feet gives a descent of about 3 feet; then another steep slope begins. The first point at which bedrock floor is found within the cave is 120 feet lower than the point of entry. It is supposed that the drainage to which the cave owes its origin was outward; if this was the case the floor must be more than 120 feet below the roof at the doorway. While this may be true, it is not indicated by the condition of the visible strata. For about 50 feet outward the side walls are nearly parallel and nowhere more than 30 feet apart. Then they terminate at an angle in the outcrop of the ledge along the hillside. The appearance and condition of the upper strata, together with this narrow separation of the side walls outside the cave, produce the impression that at a period not very remote the roof of the cavern reached to the outcropping ledge in which the walls end. Even though the rock floor should be at the great depth supposed there is a possibility that an earth floor could be found below the detritus which has accumulated since the roof fell in or has worn away.

To test the matter a shaft was begun at a point 16 feet in front of the doorway. This was as near as such work could be done without interfering with the advent of visitors, and allowed a margin of 30 feet toward the outer slope. The shaft, 6 feet in diameter, soon passed into a compact mass of red clay filled with rocks of various sizes. At 14 feet down this was broken by an irregular stratum averaging a foot in thickness, of coarse sand or fine gravel with a slight admixture of clay, such as would form in a running stream. Its slope was inward or toward the cave. As there are sandstone ledges on the hillside above, this sand may have come from them, but, if so, it is singular that none appeared elsewhere. At 18 feet down was a mass of travertine measuring nearly 3 feet across and from 6 to 12 inches thick. It had formed around the lower part of a stalagmite 18 inches long, and the bottom of the whole formation rested horizontally on clay. This gave the excavators hope that an earth floor had been reached, as the stalagmite was vertical and resembled in all respects stalagmites in the cave. But it was soon found to be a foreign inclusion, and the same confused mixture of clay and stone continued below as above. Various fragments of stalactites and stalagmites were found as part of the detritus. These, especially the vertical one, seem to confirm the supposition that the roof reached out this far at a period which is quite recent as compared with the age of the cave.

To a depth of 25 or 26 feet the task of excavating was as tedious and difficult as digging up a much-traveled, rocky road, the earth being dry enough to scour the shovels. Then the earth grew moist and within 2 feet was muddy. Cavities appeared, into some of which a switch could be thrust 3 or 4 feet. Where such a cavity extended under a large stone, stalactites were in process of formation. Soon the earth began to work into a soft mud under the feet of the workmen, and at 32 feet particles and small clods were noticed falling from the sides of the shaft. A foot lower this breaking away became more decided. It may have been due merely to the loose condition of the wet earth allowing unsupported portions to fall from the freshly exposed surface, but there was also the risk that the softer earth was sliding under the weight of that above. The workmen, two of whom were experienced well and cistern diggers, declared the risk too great and demanded to be brought to the surface.

The depth reached by this shaft was at least 5 feet lower than at any point inside, within 200 feet of the mouth of the cave. The material, with the exception of the sand layer, was almost identical from top to bottom, there being no apparent difference other than increase of moisture in the lower part. The only explanation suggesting itself at present is that the chasm is filled with large loose rocks up to a point near the bottom of the shaft; that débris from the hillside above has covered these more rapidly than it could settle in the crevices and cavities among them; and that water which makes its way downward finds some obstruction to its free passage out at the bottom of the chasm.

The only safe plan of excavation seems to require the removal of all the earth between the side walls to a depth below the mud. If the rock bottom, or any solid bottom, is at a depth of 120 feet, there is small chance that man lived in this region at a time when it was easily accessible.

Saltpeter Cave.—This is about 600 yards northwest of Wyandotte Cave. "The entrance, in a side of a ravine, is 5 feet high and 19 feet wide. Once within, a gigantic room expands, 220 feet long, 75 feet wide, and 10 to 30 feet in height, with smooth flat ceiling and earthen floor, the latter descending and with its edges much encumbered with fallen rock." [W.S. Blatchley.]

From the description given, this would seem an ideal site for research. Unfortunately, the bottom of the ravine is not more than 5 feet lower than the top of the talus at the entrance. This slight elevation is the only barrier which keeps the surface water from flowing in, and while the ravine seldom has any water in it, there would be enough after a moderate rain to drown out the diggers who were working below its level if the bank were removed.