. The Quarterly journal of the Geological Society of London. is notgenerally possible to draw a sharp line of distinction between thesedifferent phenomena, but viewed as a whole the results are suffi-ciently characteristic. Moreover, the gradual appearance of thesefeatures, as the dykes are traced from the quartz-felsite into thesedimentary strata towards the east, is a proof that the deformingagency operated from an easterly direction. IV. Conclusion. In view of the phenomena described in the foregoing pages, it doesnot seem possible to escape from the conclusion that we have in theLlyn-Padar
. The Quarterly journal of the Geological Society of London. is notgenerally possible to draw a sharp line of distinction between thesedifferent phenomena, but viewed as a whole the results are suffi-ciently characteristic. Moreover, the gradual appearance of thesefeatures, as the dykes are traced from the quartz-felsite into thesedimentary strata towards the east, is a proof that the deformingagency operated from an easterly direction. IV. Conclusion. In view of the phenomena described in the foregoing pages, it doesnot seem possible to escape from the conclusion that we have in theLlyn-Padarn dykes a result of the deep-seated conditions prevailingduring the latest stage of the Bala eruptions. These dykes appear tohave been filled with a magma rather more basic than the Bala mineralogical evidence seems to point to a larger proportionof titanic acid, and to a greater amount of lime and magnesia. Thesomewhat-remarkable chemical analysis by Dr. Ycelcker,1 of a rock 1 Geol. Mag. 1868, p. 125. Quart. Journ. Geol. Soc. Vol. LX, Pl.
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectgeology, bookyear1845
