yellowish and earthy when going to decay. There is some hornblende disseminated throughout the mass: a few crystals of lamellar and transparent felspar are also imbedded in the basis. The rock acts strongly on the magnet. It emits when breathed upon a sensible argillaceous smell.
†††† Sienite.
I noticed but one block forming part of the Druidical barrow already spoken of. The texture is unusually close. The two ingredients are crystallized and intimately blended together. The felspar fuses, but not readily, into a transparent enamel which is not frothy. There are besides in the mass some very minute crystals, of an yellowish colour with a vitreous lustre. (Qu. garnets?) Specific gravity 2.932.
††††† Quartz.
Several blocks of white and greasy quartz, some of which contain yellowish talc, form one of the circles of the Druidical barrow in Kirk Ballaugh. Sp. gr. 2.536.
†††††† Garnet Rock.
This rock, of an unusual occurrence I believe, I found under the form of water-worn pebbles on the shore at Kirk-michael, and as this is no place for vessels to lie at anchor, I have no reason to think they could have been taken as ballast and thrown away where I remarked them. The rock is highly magnetic, very hard and tough. The mean specific gravity 2.967, the extremes being 3.085 and 2.846. The mass is of a liver-brown colour, with many crystals of an orange or reddish-brown cast imbedded in it. Their
