Thus, between tide-waves and currents, changes are going on continually both in the volume and the physical constitution of the sea-water. And this, which might at first on a hasty glance look like casual and unimportant variation, when we come to consider it attentively, is found to be an arrangement fraught with wisdom and beneficence; for it insures continual variations of temperature, it attracts the purifying storms, restores the elastic spring of the atmosphere, and provides for weary man a healthy tonic breeze when he rambles along the beach or scales the face of the cliff. Without the motion imparted by the tides, the sea would probably become putrid. Now the tides depend upon the MOON; yet how seldom do we think of her invaluable services, when we gaze upon her pale face! An Italian once told me that he “loved the moon, adored the moon, never tired of looking at the moon.” And the Padishah,[4] I have heard say, prefers “moon-faced” ladies for his soft companions; but I doubt whether either the pensive Italian or the glittering lord of the Bosphorus ever bestowed five minutes’ thought on the mighty phenomenon of the TIDES. There are other changes in what may be termed the tidal “high-water mark,” due to the lapse of ages, which the sea has chronicled on the face of many a shore and cliff. It is well known that the coast-line, in this and other countries, has experienced many alterations as to its level. In some places, the ocean has apparently encroached upon the land; in many others, it has receded. One striking _index_ of this latter, and which may be implicitly trusted as proving the fact, occurs where the waters have retired from their former level, and have left exposed to view the remains of an ancient _beach_. Thus, between Brighton and Ovedean, is found what goes by the name of the “Elephant-bed,” because such fossil bones lie among the pebbles in this part of the cliff. The entire stratum undoubtedly was at one time a beach. Similar phenomena have been traced along the coast-lines of Arbroath and Cromarty shires. Elsewhere, the sea has gained upon the land; undermining the friable sandstone cliffs, and, as it were, melting down the headlands, so as to change the outline of the coast. But in these latter instances, although “terra firma” has given way, it may be doubted whether the water itself has _risen_. Wherever it has indubitably done so, to the extent _e.g._ of submerging a village, I should apprehend the presence of volcanic agency. [4] Sultan, “Father of the Faithful.” CHAPTER IX. GEOLOGY LIES AT THE BOTTOM OF EARTHLY THINGS. There seems to be no strong reason for doubting that every elementary substance of which we have any knowledge was _separated_ at the first from that crude mass called “the earth,” and which, along with “the heaven,” God created in the beginning.