Where the water-level was constant for a considerable time, during which banks were formed, they show by their height above the present flow of the water how much the condition of the latter has been changed. When two such banks lie one behind the other, at the same level, or successively like terraces, we are justified in concluding that the level of the water has changed and the land been increased, or that the one has sunk and the other in consequence advanced upon it. In confined basins this sinking may have been the consequence of the outlet widening by wear, and in open seas by the upheaving of the land. On all the large lakes of Finland are seen banks and terraces, as well as single blocks of stone, on the slopes. The terraces often lie one above the other, which indicates sudden depressions of the water’s surface at different periods, each bank or terrace marking the water-line of a particular period, in which were deposited in strata many kinds of detritus mixed up with vegetable substances.” These remarks of Boethlingk, originally recorded in the “Bulletin of the Academy of Sciences of St Petersburg,” are here cited from the “Neues Jahrbuch von Leonhard und Bronn.” They are valuable, as results of personal observation, and have doubtless already given a tolerable inkling of the reasons upon which this species of explanation of the phenomenon of boulders has been founded. Captain Bayfield, of the Royal Navy, the able surveyor of the Canadian lakes and of the river St Lawrence, records similar facts observed by him in that river. The St Lawrence is in winter low, and the ice on the shallows along both banks of the river is frozen into one connected mass by a temperature which often sinks to thirty degrees below zero, or sixty-two degrees below the freezing point. When the thaw sets in, these masses are raised up and floated away, and with them an extraordinary quantity of blocks and stones which had been encased by the frost in their substance. In like manner, anchors which for the security of the ship in winter had been fixed near the shore, were obliged to be cut out of the ice, or they would have been carried away. Half a ton weight of one of the strongest chain cables was torn off and carried many yards away, when means were taken to cut it out. Captain Bayfield also mentions the fact that he had often seen at sea icebergs laden with stones, in the Straits of Belleisle the captain examined one amongst many which must have come from Baffin’s Bay; it was thickly covered over with blocks, gravel, and stones. M. Reinecke, an officer of the Russian navy employed on a survey of the coast of Finland, relates two pleasing though minor incidents of a similar kind. The fishermen of Sweaborg pointed out to his officers that the sea-bottom of their coast was subject to frequent change, partly from the action of the waves in violent storms, but more particularly from the force of traction exercised by enormous bodies of ice which