In fine, we cannot quit the subject without being convinced that these ceaseless changes afford one of the grandest examples of that continuous series of mutations--cycle and epicycle--which has been already alluded to as a distinguishing feature in all the operations of Nature. We are accustomed to think and speak of "the everlasting hills." We look on the solid lands whereon we dwell as the emblem of all that is stable and steadfast, and on the boundless ocean as the type of all that is unsteady and changeful. The traveller who stands on those plains where the human race was cradled, marks still the same valleys with their winding rivers, still the same rocks and hills, still the same blue sky overhead. The dust of centuries has gathered over the graves and the dwellings of the early races, yet the covering is but thin, and if we could conjure from their resting-place some of these venerable patriarchs, they might perhaps see little or no change on the haunts of their boyhood. We feel it otherwise, however, when we contemplate the ocean. In sunshine and in storm its surface never rests. The wave that now breaks against some bald headland of our western shores may have come sweeping across from the coast of America, and the broad swell that rolls into surf along the shores of Newfoundland may have travelled from the frozen seas of the North Pole. And so it has ever been; the "far resounding sea" of Homer is the "far resounding sea" still; and the "countless dimpling of the waves," invoked in his agony by the chained Prometheus, remains restless and playful as ever. "Firm as a rock," and "fickle as the sea," have therefore become proverbs of universal acceptance. Yet when we investigate the matter as we have done in this and the preceding chapter, it appears that an exactly opposite arrangement would be nearer the truth. It is the sea that remains constant-- "Time writes no wrinkle on its azure brow;"