Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/224

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here and there in the flat ground of Stretton valley; they rest on the aggregate sandstone already mentioned, and rise E.S.E. at a small angle towards the Lawley and Caer Caradoc, in the parallel of which they are situated, but they entirely cease in the more contracted part of the valley, a little further to the south, where the trap of Ragleath hill is evidently incumbent on the transition (or, perhaps, newest primitive) clay slate, which breaks out to-day in the streets of Church Stretton.

From these facts it appears that the line of elevated ridge-hills from Lilleshall to Ragleath is an unstratified mass of rocks of trap-formation incumbent on highly elevated strata of transition slate: that on the eastern side of this mass there is a great deposit of stratified rocks, consisting of quartz-grit ; of a micaceous sandstone nearly allied to greenstone; of a sandy slate-clay; of limestone, slaty marl and sandstone slate in alternating beds; and of the independent coal-formation: all rising up parallel, or nearly so, with the trap at a horizontal angle, the magnitude of which decreases, in proportion to the distance of each bed from the trap, unless where interrupted by casual and local causes. That on the western side of the trap, the mass of deposits is very small, consisting of a sandstone composed of angular fragments, on which rests a thin broken coal-formation. That the old red sandstone bounds the whole of this series of rocks on the east, north, and north-west, but though in contact, appears to be perfectly unconnected with them.

The trap-formation itself does not seem to correspond with any of those described by mineralogical writers, and its essential characters are, its unconformableness with the transition slate on which it rests, the great abundance of claystone, both massive and vesicular, which it contains, and the presence of actynolitic amygdaloid.