DEPOSITS OF ASSYKT.

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Or why should the red, rough-grained sandstone, with its in-cluded pebbles, which occupies the first place in the systemof the east coast reckoning upwards, occupy also the firstplace, reckoning upwards, in that of the west coast, and notthe place of any of the three beds which overlie it ? Or, fur-ther, why should the place of the two great sandstone beds ofthe east-coast system, in their position as second and fourth,be occupied in the west-coast system by arenaceous beds alsosecond and fourth in the series, instead of being occupied bybeds not arenaceous ? The number of the chances againstsuch thorough coincidences as that exemplified here, regardedsimply as chances, are so great, that they will be found tooccur in no two British systems not identical. The proba-bility, so to speak, that an unaltered system which in onelocality is fossiliferous in one of its beds and non-fossiliferousin any of the others, should in another locality be slightlyaltered in all its beds, and, in consequence, non-fossiliferousin them all, is a probability which must be regarded as hay-ing many more chances in its favour.

Let me also remark, that the Old Red system of the eastcoast, which rests, as I have said, on the unconformable gneiss,is overlaid in several localities, as at Eathie and Shandwick,by beds of the Liassic formation. A wide gap occurs in thegeologic scale in these northern districts : the Carboniferous ,Permian, and Triassic systems, are wanting ; and along thenorthern side of the Moray Prith generally the Old RedSandstone forms the immediate base of the Lias,—a forma-tion which, though it barely appears on the edge of the landthere, is apparently largely developed under the bed of theGerman Ocean. And it is worthy of being noted, as bearingon our question, that the Scottish Lias of the Atlantic holds—as at BroadfOrd and Applecross—exactly the same rela-tion to the Red Sandstone of the west coast that the ScottishLias of the German Ocean does to the Old Red Sandstone of