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ADDITIONAL BRITISH LOCALITIES. 431 with carbonic acid. This last oxide, during the process of calcination, is converted into the red oxide, and being mixed with the lime, occasions it to assume a reddish- brown colour. See Dr Thomson’s phemistry, vol. i. p. 391. The lepidolite in the limestones before mentioned, oc curs in fine distinct granular concretions. These sub stances are of a white colour, and are either transparent or semi-transparent. The hornblende, when present, has also a fine granular form, and is slightly attracted by the magnet. These limestones, on account of the hard fo reign bodies which they contain, are capable of cutting glass, and of yielding a few feeble sparks to steel. The lepidolite mentioned by Klaproth, when exposed with soda to a red heat, and melted, exhibited a mass of a yellow colour, with red and blue spots, according to the oxidation of the manganese contained in the minerals. Hut the lepidolite which is present in these limestones being, free from manganese, or any other metallic body, exhibits only a yellow globule when fused with soda.” Finite.—In porphyry in Ben Gloe, and Blairgowrie. M. Serpentine.—Bervie, and Cortachie. 'Fremolite, jibrous, common, and glassy.—In limestone, Glen Tilt. M. Diallagc —Island of Coll. M. , a,i nr Hypcrstene.—In syenite at Loch-Scavig, in Skye. M. Also near Portsoy. Schiller spar.—In serpentine at Cortachie. Sahiite.—In limestone in Glen Tilt; and in primitive rocks in Glenelg and Rnnnoch. M. Also in the island of Unst. Fibrous
