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10 HORNBLENDE FAMILY. Chemical Characters. Before the blowpipe, it melts into a black glass, but is rather more refractory than common hornblende. Constituent Parts. Basaltic Hornblende from Fulda. Silica, - . - 47.00 Alumina, - - 26.00 Lime, - 8.00 Magnesia, - . 2.00 Oxide of Iron, - 15.00 Water, ... 0.50 08.50 Klaproth, Beit. b. v. s. 154.. Geognostic Situation. It occurs imbedded in basalt, along with olivine and augite; also in wacke and trap-tuff; in small quantity in some kinds of porphyry, and frequently in lava. Geographic Situation. Europe.—It occurs in the basalt of Arthur’s Seat, and other similar hills around Edinburgh ; also in the basalt of Fifeshire, and that of the islands of Mull, Canna, Eig, and Skye. It is also an inmate of the basaltic rocks in England and Ireland. Upon the Continent, it is very widely and abundantly distributed: thus, it occurs in the floetz-trap rocks of Fulda, the Saxon Erzgebirge, Bo, liemia, Silesia, Bavaria, Austria, Stiria, Hungary, Tran sylvania, Italy, France, and Spain. America.—It is frequent in the basaltic rocks of Mex ico. ' Observations.