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238 OXIDES, EAKTIIS, AND ACIDS. Analyses of hematite from Tavetschthal by v. Kobell: In attached crystals; hotryoidal, reniform and fibrous masses; scaly, granular and earthy; pseudomorphous after magnetite, pharmacosiderite, fluor, calcite, gothite. Hematite occurs chiefly in beds and veins'in the older rocks, and as an ingredient of some rocks. It is deposited by sub limation in the crevices of active volcanoes, not unfrequently, at the present time; also in pottery furnaces where salt is used for glazing. Is found crystallized in Elba, St. Gotthardt, Caravatti in the Gnsons and many other parts of the Alps, Eramont in the Vosges, Altenberg and Poberschau in Saxony’ Capao in the Brazils, Thumberg near Elachau in Salzburg; imbedded in the dolerite of the Meissner, near Hedemiinden in the valley of the Werra, St. Just and Tin Croft mines in Corn wall, Cumberhead in Lanarkshire, Schabrowski near Katha- ripenburg in Siberia. Crystals formed by sublimation are found on Vesuvius, Aitna and Stromboli; Puy de la Vache and Puy de la Ghopine in Auvergne, Jumilla in Murcia, in crevices of syenite at Meissen in Saxony, lteps and Magyar-llerniaiiy in Transylvania. It occurs in thin scales (micaceous iron) in the Eichtelgebirge in Bavaria, Bcichenau in Bohemia, Golnitz and Dobsehau in Hungary, in mica slate (itacolumite) in many parts of the Brazils, near Tavistock in Devonshire, near Duu- keld in Perthshire, Constantine in Estremadura, Hawley in Massachusetts, Stiria, Carinthia, Moravia, the llarz, Sardinia, Siberia. It occurs massive in beds in Elba, in Sweden at Gel- livara in Lulea Lappmark, Norberg, Grengesberg, Langban- shytta; Kalstadt mine near Krageroe in Norway, in the Harz, Salzburg, the Tyrol, Ilessia, Westphalia, Saxony, Bohemia, Wiirtemberg, Lancashire, Cumberland, North America, Asia, Africa. It occurs pseudomorphous after magnetite at Inficio- nado in Minas Geraes in the Brazils, after calcite at Sundwig near Iserlohn, after gothite at Lostwithiel in Cornwall. According to Mohs ri* = 91° 2', while according to Phillips rr 1 = 93° 6o', a value agreeing very closely with the measures obtained from a very good crystal, evidently formed by sublima tion, and affording the characteristic red streak of hematite. The latter value has consequently been adopted in the present treatise. When the vapour of chloro-ehromic acid, CrCi’0r ! , is trans- Bed oxide of iron Protoxide of iron . . Titanic acid . . . 94-82 trace 3-57 1‘61 Protoxide of manganese