IDOCHASE. 329 inner blowpipe flame melts into a red glass. "With boras fuses into a green glass. With soda yields metallic copper. According to Magnus after fusion G = 2 - 95. According to Varrentrapp fusion reduces g from 3'346 to 2'929...2'9<u. Ca’Si 2 + AlSi, a portion of the Ca being replaced by Mg, Te, Ain, and part of the Ii by p*. . -^u the three analyses by Hermann the quantities of oxygen in the bases b, b and in the si are as numbers 3, 2, 5 nearly. Analyses of idocrase a from Egg near Christiansand, b from w.iklowa in the Banat, c from Vesuvius, d from Slatoust, all Silica . , . Alumina . . Lime . . Protoxide of iron Magnesia . . l’rotox. of manganese Slatoust by Varrentrapp:— a b c d e / 37*60 38'52 37-30 37-18 37-55 37'84 17'70 20*06 23-63 1811 17-88 17-99 31'9() 32-41 29-08 36-79 36-56 36-18 6'49 3’42 3'99 4-07 6-34 6*45 4'64 0'60 2-99 1 0-02 1 t 6-21 0-77 1-60 2-02 2*81 Analyses of idocrase g from Vesuvius, h from Piedmont, * from the valley of Sass, all by Karsten, k from Monzoni by v. Kobell, I from Gockum by Berzelius, m from Erugard by Nordenskidld:— Silica .... Alumina . . . Ked oxide of iron Protoxide of iron . Lime Magnesia . . . . Protox. of manganese Analyses of idocrase n from a place to the east of Kongsberg V Bammelsberg, 0 from the Wilui river in Siberia, g = 3-375, P from Achmatowsk in the district of Slatoust, o = 3'40, q from Poliikowsk in the district of Slatoust, g = 3'42, all by Hermann, r of a partially decomposed variety from Ilaslau near Eger b y Karsten, s irom Ala by v. Kobell:— 9 h i 1c I m 37-50 39-25 38-40 37-64 36-00 38-63 18-60 18-10 18-05 16-42 17-50 17-40 6-26 (Na 0’90) — 6-25 — — 4-30 3-10 6-42 — 3'90 33-71 33’85 36 72 38-21 37'65 27'70 3-10 2'70 1-60 — 2'62 10-60 O'lO 0-75 065 (H 0'30) 0*33 Silica Alumina . . Led oxide of iron . n 0 P ? r 8 3724 38-23 37-02 38-19 39-70 34*85 10'80 14-32 13-25 14-35 18-95 2071 7'21 6'34 7'12 5'20 —