Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/280

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as to admit of the conversion of its siliceous layers into the substance now found interstratified in the limestone, while this latter resisting as it is well known to do, any change from the application of heat under such circumstances, might undergo no other affection than I that softening which has led to its flexure and contortion.

The remaining appearances to be seen at this rock are more curious as adding to the unexampled confusion of the whole mass, than as offering any thing very new to the geologist in addition to that which has been already detailed.

Among the remaining substances entangled in this confusion, a large vein of felspar is the most remarkable. Its course is not long, nor does it appear to have any connection with the granite. It varies in colour through this limited extent, being sometimes white, at other times of a pink or dead lilac hue, and in some few places greenish. This latter colour seems to proceed from a mixture of epidote, which mineral is found in other parts of the rock in thin veins accompanying the granite and colouring the schist. Some massive garnet is also to be seen involved among the other substances, and it seems principally connected with the limestone. In a few cavities there occur crystals of flesh coloured calcareous spar, but so incomplete from the narrowness of the spaces in which they have crystallized, that I could not assign their figure. This I believe completes the catalogue of the minerals found in this singular place.

The granite is again seen crossing the river between this bridge and Forest Lodge, and near it lies a body of quartz rock which is evidently a continuation of some beds which may be observed in the hill above.

About 300 yards below the Lodge it crosses the stream again, and here the limestone is again mixed with it. A set of beds of a yellowish and greyish colour, resembling some varieties of foreign