Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/198

 It is occasionally mixed with the stilbite, but is also found in very large masses, either alone or intermixed with crystals of calcareous spar. These masses have fallen from the cliffs above, and lie detached on the shore. They consist principally of a confused crystallization, but cavities are also found in them in which the mineral has crystallized at liberty and in its regular form. These crystals exceed a quarter of an inch in length, and the substance is here invariably of a white colour. There is nothing more remarkable in this mineral than the contrast between its present and its original state with respect to hardness. The lumps which I have described sometimes exceed twenty pounds in weight, yet they remain entire on the beach notwithstanding they must have fallen, together with the other rocks which are here found, from an elevation of many hundred feet. At the present time the slightest contact causes them to crumble into atoms.

To the varieties of analcime which were formerly enumerated I may add another which is also to be found at this spot. It is of a brick-red colour, but not crystallized, and is largely mixed with the amygdaloidal rock that predominates at this place.

I formerly mentioned that epidote was found crystallized in cavities of the different trap rocks both in Garsven and in Glamicb. In addition to that, I may here say that fragments of the same rocks are to be found at the foot of the former hill, in which this mineral appears to form a constituent part of the trap, being uniformly mixed with the other ingredients throughout the whole mass.

It has been said in some of the popular accounts of Scotland, that agate pebbles were found near Dunvegan, but having never seen specimens from Sky, and doubting the authority on which the report was founded, I took no notice of this circumstance in the former paper. I have now however found them, although in no great