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carbonated potafh, and tbe precipitate thus ob-tained, after being wafhed and dried, was againdigefted with muriatic acid, which left behind23 grs. of filex.

c. The preceding folution was now com-bined with cauftic ammonia, which threwdown 62 grs. of a yellowilh white precipitate,that was fubfequently reduced by ignition to33 grs. and was pure oxyd of titanium.

d. The refidual fluid when faturated at aboiling heat by mild potafli, afforded 33 grs. ofcarbonated lime.

1 he menachanite of Bavaria was thus ana-lyfed by Vauquelin. c

a. xoo grs. finely pulverized were melted ina filver crucible with 400 grs. of cauftic potafli,during an hour and a half. The fufed mafswas of a green colour, and afforded with watera green folution, a brick red powder weighing124 grs. remaining behind.

b. The above 121 grs. were boiied for anhour with cauftic potafh, and the folution afterfaturation with muriatic acid was treated withcarbonat of potafh, which threw down 3 grs.of oxyd of titanium.

c. The refidue of the 124 grs. was digeftedwith dilute muriatic acid, which foon acquireda yellow colour, and left behind 46 grs. of areddifli white powder, which was oxyd of tita-nium.

d. The yellow muriatic liquor was faturatedby ammonia, and afforded 50 grs. of brownoxyd of iron.

e- The green alkaline folution fa) was fu-perfaturated with muriatic acid, and acquired abright red colour, which during evaporation en-tirely dilappeared. The faline refidue wasa gain perfectly foluble in water, thus fhewingthe total abfence of filex •, on the addition ofcarbonated potafli, it yielded a precipitateweighing 2 grs. which was carbonated man-ganefe.

§• 3. Chemical Properties.

Several attempts, though with but imperfeftfuccefs, have been made to reduce titanium tothe metallic ftate. The fait feledled for thefeexperiments by Vauquelin, d was the carbonat,which after being formed into a pafte with fiflioil, was placed in a crucible lined with a mix-ture of clay and charcoal, and expofed for threequarters of an hour to an intenle heat. Ablackifh fpungy mafs was thus obtained, whichin fome parts prefented a reddilh metallic ap-pearance.

In'another experiment ico parts of native* Journ. des Mines, No. 1$. p. 58.

titanite were mixed with 50 parts of calcinedborax, and an equal quantity of charcoal; themafs thus produced was placed in a lined cru-cible, and heated for an hour and a half in aforge furnace. An agglutinated brittle mafswas thus obtained, the external colour andluftre of which greatly refembled that of cop-per. Being broken and expofed to the airwhile it was yet hot, its red colour palled infome places to purple and then to blue. Lam-padius e is faid to have fucceeded ftill morecompleatly, by decompofing the gallat of tita-nium by means of fixed alkali, and ftronglyheating the oxyd thus obtained in a charcoalcrucible. The refult of this procefs is a me-tallic mafs of a dark copper colour with confi-derable brilliancy; it is very infufible, is com-pofed of llightly cohering fcales which indivi-dually are moderately elaftic. It tarnilhes byexpofure to the air, is converted by heat to ablue oxyd, detonates with nitre, and is readilyafted on by all the ftrong acids. The metallicmafs obtained by Vauquelin, exhibited the fol-lowing properties with acids. The nitro-muri-atic acid converted it fuperficially into a whitepulverulent oxyd. The muriatic acid difen-gaged a large quantity of hydrogen gas, and aconfiderable quantity of white flocculent oxydwas obfervea floating in the liquor. Concen-trated fulphuric acid at a boiling temperature,diffolved a portion and converted the remainderto a white oxyd, fulphureous acid gas beingdifengaged; and the fulphat of titanium thusproduced exactly refembled that obtained by theoxyd of this metal.

Titanium appears capable of three ftates ofoxydation, diftinguifhed by the colours blue,red, and yellowilh white, the latter being thefaturated or per-oxyd. With regard to theproportion of thefe two ingredients in the dif-ferent oxyds, fcarcely any thing certain isknown, only it may be concluded with fomeprobability from the refult of an analysis byVauquelin, that the red oxycl in palling to theftate of white oxyd acquires about 18 per cent.From the fame experiment by Klaproth indeed,it would be concluded that the augmentationwas about 24 per cent. ; the difference is notvery great, and the truth may perhaps liebetween.

The white oxyd when heated acquires alemon yellow colour, which however disappearsagain in proportion as it cools. In this ftate ityields a little to concentrated fulphuric acid,but is not diffolved by any other liquid men-• Phil. Maj. Yol svii. p. 95,

* Ditto, No. ij. p. 21 .