. The Quarterly journal of the Geological Society of London . n Relation to the Flaggy Gneiss.—In his laterpapers, Murchison admitted that the limestone was separated fromthe flaggy beds * by a great fault, by which the upper quartzite was thrown down out of sight; but he, notwithstanding, held thatthe limestone was overlain by the upper series of quartzose andgneissic rocks, apparently on the ground that both dipped in thesame direction, to the east. Admitting his facts, his reasoning isobviously fallacious, and might be employed to prove the most op-posite conclusions. But I cannot accept hi
. The Quarterly journal of the Geological Society of London . n Relation to the Flaggy Gneiss.—In his laterpapers, Murchison admitted that the limestone was separated fromthe flaggy beds * by a great fault, by which the upper quartzite was thrown down out of sight; but he, notwithstanding, held thatthe limestone was overlain by the upper series of quartzose andgneissic rocks, apparently on the ground that both dipped in thesame direction, to the east. Admitting his facts, his reasoning isobviously fallacious, and might be employed to prove the most op-posite conclusions. But I cannot accept his facts. Neither thelimestone nor the flaggy group dips to the east. The true relationsof the two formations are shown in the annexed plan (fig. 1), whichis, in outline, a reduced copy of the new ordnance map. The mostimportant dips are shown by arrows. * These flags are a true schist, though they are far less coarsely crystallinethan the Lewisian. 240 C. CALLAWAY ON THE LIMESTONE Fig. 1.—SJcetcJi Map of the Durness Area.(Scale, about | inch to 1 mile.). The fault fl runs from sea to sea, east and west, exactly at thebase of Far-out Head, which is entirely composed of thin-beddedgneiss and quartz-schist, dipping steadily to the north-east, exceptat some points a mile north of the fault, where the dip is conse-quently unimportant. West of the ruined church, where the limestone contains numerousfossils, the dip is north-east, so that it might seem as if it passedbeneath the schist. But here the nearest exposure of the latter isover half a mile to the north-east, the intervening area being occu-pied by blown sand, so that no junction can be seen. Further ex-amination proves that this dip of the limestone is exceptional. Following the strike of the schist to the south-east, we trace itright up to the fault. Both rocks are here clearly exposed, the flagson the shore and in the adjoining field, and the limestone in a lowcliff, which is an inland extension to the west of the preci
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