Excavations here, while quite desirable, would be very expensive. Much stalagmite would have to be blasted; upward of a thousand yards of earth moved, and all of it taken out of the cave, because there is no room for it inside. As a man can not push a wheelbarrow up such an incline, a trench must be cut through to the exterior slope; and as solid rock lies not more than 5 feet below the surface at any point, blasting would be necessary the rest of the way. The task is equal to opening a stone quarry.
The second cave on McDerment's place has a good opening. A trench 4 feet wide and 6 feet deep where the rock is thickest has been blasted out to make a level approach to the entrance. Masses of stalagmite on each side, sloping like solid rock from the walls, leave barely room for a man to walk for the first 30 feet. Here the walls recede somewhat, and a pit nearly 15 feet deep yawns before the explorer. After continuing for some distance with this depth, there is another drop of 10 feet which holds until the end of the cave is reached. This entire depression is due to the removal of earth for making saltpeter. It is evident that a vast amount of material has been carried out.
As in the first cave, excavation would be very difficult and expensive. All rock and earth would have to be carried up a steep grade, or a deep cut made to wheel it out. As the light is very dim at the first widening of the walls, it is not probable the space farther back would be occupied unless as a refuge.
Both caves were eroded by water running into the hill, and the end of each is abrupt, the roof being higher and the walls farther apart than at any point nearer the entrance. The original outlets are now filled with earth, and apparently have been so for ages.
Fort Deposit Cave.—Six miles below Guntersville the highway to Huntsville crosses the Tennessee River at Fort Deposit Ferry and passes out through a narrow valley between two bluffs. Less than 100 yards above the landing, on the north, or right, bank, is a large cave from which the spot takes its name; there being a tradition that it was used by General Jackson as a storage room for supplies during the Creek Indian war. On either side the bluff is vertical to the water's edge, making the cave now inaccessible except by boat. In front of the entrance the rock is worn in ledges which can be easily ascended.
Fig. 23.—Cross section of Fort Deposit Cave at 18 feet.
The opening or mouth of the cave is oval in form, about 18 feet high and 15 feet wide. The sides are uneven, there being a projecting shelf on each side near the floor. At 40 feet from the opening these disappear, owing to the narrowing of the cavern. There is a gradual ascent of the floor toward the rear, the rise being about 2 feet in the first 60 and more rapid from that point onward. A thin deposit of dried mud on each side, where it escapes the feet of visitors, shows that the river enters the cave at times, but not to a depth that carries it back more than 25 feet. The present ferryman says the flood of 1867 is the only one which has reached so far within that period.
After clearing away the earth, roots, and rocks at the front, a straight vertical face at a distance of 18 feet from the entrance measured 9½ feet at top and 5 feet at the bottom between the solid rock wall on each side, and was 4 feet 4 inches high. The floor was not of solid rock entirely across, there being a crevice less than 4 feet wide which was not cleaned out, because no one could have lived in it. About the middle of this bank (vertically) streaks of red earth, burned elsewhere, extended 3½ feet out from the right wall; there was very little ashes and no charcoal mixed with it. Above this red the earth was dark like garden soil and contained a few shells and fragments of pottery, with a little charcoal and ashes; it had all been disturbed and apparently resulted from scraping the débris away from camp fires. Below this, the line of demarcation being very distinct, the earth was yellow and sandy, like river bottom land, and contained no foreign matter except roots of trees growing outside. Figure 23 shows a section on this line; the crevice is omitted from this and the subsequent illustrations.