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Rh almost fills, and up which the boat can no longer proceed. Yet far beyond, where all is opaque darkness, one still hears the muffled wash and sob of the waves as they ceaselessly eat and eat into the hidden bowels of the rock. As the whole force and vastness of the ocean lies beyond this little tip of its tongue, to where may not such burrows extend? and might not, by a knowledge of their position and the direction in which they run, some inland towns be supplied with the blessing of sea-water?

The water in these caverns is delightfully clear, revealing in every detail, through its lucid green, the smooth-rolled pebbles and great white rounded boulders which strew, or rather make, their floor. To look down at them is like looking up into the arched roof of some other cave. One might think it the reflection of the one overhead, till, glancing up, the difference is remarked—jagged, bright-hued peaks and niches instead of smooth, even whiteness. This effect, as of a roof beneath one, is due, I think, to the continuation downwards of the sides of the cavern, for this gives the same vaulted appearance, but reversed, that there is overhead, and the mind, as with the image on the retina of the eye, soon sets it the right way up.

These caves must have been known from time immemorial to as many as were accustomed to coast round the island, and it is interesting to think of who, and what kind of craft may, from age to age, have visited or sheltered in them. Recently,