Where the great spring forces its way to the surface, the water is a deep, brilliant blue with white caps, and its falling weight keeps clear of moss a large spot of fine, pure, white sandstone, while all the balance appears a vivid green from the moss that thrives beneath the moving water; and surrounding these are the handsome, foliage-decked grey walls. The edges of the basin are thickly strewn with fallen rocks deeply covered with moss, in which small ferns are growing, and on these gay stepping stones we crossed to the head-wall of the canon to find ourselves at the open mouth of a cave from which flows a clear, shallow stream to join the waters of the Spring in that wonderful basin. The entrance to the cave is an arch about fifteen feet wide and twelve feet high, with the clear, shallow stream spreading over the clean rock floor from side to side. Here now was presented a difficulty. Truly the cave was _not_ quite dry. The water was about ten inches deep, and my boots in Thayer. Contrary to advice, however, my nephew had brought his, and with a boy's kindness loaned them while he made the trip with bare feet and rolled up trousers. A short distance within, the cave widens and the floor of the extension being somewhat higher, is dry, but the roof drops so low over it that the water-course is an easier route of travel; and this soon widens into a lake above which the ceiling rises in a broad dome less than twenty feet in height, and hung with heavy masses of dripstone draperies of varying length, from five to seven feet; and all the ceilings are fringed at various heights with stalactites of every size and age, some being a clear, colorless onyx, while others proclaim their great age in the fact that they have so deteriorated that the onyx texture is either partly or completely lost, and what was once a pure drip crystal has returned to a common, porous, dull-colored limestone so soft that portions can be rubbed to powder in the hand. Picking the way carefully as the depth of the lovely lake increased, we followed the sound of falling water and peered into the dark distance in a vain effort to see it, yet expecting to reach that special object of interest by keeping to the shallower parts of the lake. These expectations were shattered suddenly when the boots filled with water, and that called to mind the fact that twenty-three miles and a chilly night lay between us and dry clothing; so we returned to the outside world and rested on the rocks where Captain Greer and our young driver waited for us. The cave has never been fully explored, and probably we penetrated farther than others have ever done, as the owner knew nothing of the falling water we so distinctly heard and were surely very near.