and on their floors are mounds of loose rocks, corresponding in form to the curve of the ceiling. ^ Some of these apartments are peculiarly grand in appearance. The largest is 1,000 feet in circumference and 245 feet in height, the hill in theā¦center rising 175 feet above the surrounding level. , Other chambers nearly equal this in extent andexceed it in beauty. Among the notable formations may be mentioned a stalagmite twenty-five feet in diameter and thirty feet in height, and a group of stalactites forming a semicircle, having the appearance of a canopy. Gypsum and epsoni-salts and flint in veins and nodules are abundant in many of the chambers.