carried the boughs of Birnam wood to the Hill of Dunsinane; and I soon acquired a sort of affection for certain shells, which bore, as I supposed, a more exotic aspect than their neighbours. Among these were, _Trochus Zizyphinus_, with its flame-like markings of crimson, on a ground of paley-brown; _Patella pellucida_, with its lustrous rays of vivid blue on its dark epidermis, that resemble the sparks of a firework breaking against a cloud; and, above all, _Cypræa Europea_, a not rare shell further to the north, but so little abundant in the Firth of Cromarty, as to render the live animal, when once or twice in a season I used to find it creeping on the laminaria at the extreme outer edge of the tide-line, with its wide orange mantle flowing liberally around it, somewhat of a prize. In short, the tract of sea-bottom laid dry by the ebb formed an admirable school, and Uncle Sandy an excellent teacher, under whom I was not in the least disposed to trifle; and when, long after, I learned to detect old-marine bottoms far out of sight of the sea--now amid the ancient forest-covered Silurians of central England, and anon opening to the light on some hillside among the Mountain Limestones of our own country--I have felt how very much I owed to his instructions. His facts wanted a vocabulary adequately fitted to represent them; but though they "lacked a commodity of good names," they were all founded on careful observation, and possessed that first element of respectability--perfect originality: they were all acquired by himself. I owed more, however, to the habit of observation which he assisted me in forming, than even to his facts; and yet some of these were of high value. He has shown me, for instance, that an immense granitic boulder in the neighbourhood of the town, known for ages as the Clach Malloch, or Cursed Stone, stands so exactly in the line of low water, that the larger stream-tides of March and September lay dry its inner side, but never its outer one;--round the outer side there are always from two to four inches of water; and such had been the case for at least a hundred years before, in his father's and grandfather's days--evidence enough of itself, I have heard him say, that the relative levels of sea and land were not altering; though during the lapsed century the waves had so largely encroached on the low flat shores, that elderly men of his acquaintance, long since passed away, had actually held the plough when young where they had held the rudder when old. He used, too, to point out to me the effect of certain winds upon the tides. A strong hasty gale from the east, if coincident with a spring-tide, sent up the waves high upon the beach, and cut away whole roods of the soil; but the gales that usually kept larger tides from falling during ebb were prolonged gales from the west. A series of these, even when not very high, left not unfrequently from one to two feet water round the Clach Malloch,