Barway

A pa age into a field composed of bars made to take out of the posts. Bar'wood, n. See BAPHIA. Bary'ta, BARYTES, OXIDES OF BARIUM, n. [Gr. bar us, heavy.] ( Chem.) A grayish-white porous alkaline earth, discovered by Scheele in 1774. Sp. grav. about 4:00. Its taste is harsh, and more caustic than lime, acting on the stomach as a violent poison. It turns vegetable blues green, and is a non-conductor of electricity. B.B. it fuses, and penetrates the charcoal, an effect probably occasioned by the presence of water, as it has since been found, when anhydrous, to fuse only by the strongest heat of a forge. When sulphuric or chlorohydric acid is poured on baryta, it becomes red-hot. When water is poured on it, baryta is slaked like quicklime with the evolution of heat; the ma becomes white and swells; if more water is added, so as to dilute it completely, the baryta crystallizes, on cooling, as a hydrate (BaOHO), and it then absorbs carbonic acid from the air, and must, therefore, be preserved in closely stoppered bottles. It di olves in 20 parts of water, forming baryta-water, much used as a chemical reagent. Boiling water di olves half its weight of baryta, and deposes, on cooling, four or six-sided prismatic crystals, containing 10 equivalents of water. Form. BaO. Salts of B. -1. They are generally white or colorle , and crystalline. 2. The soluble salts of baryta give a white precipitate by sulphuric acid and alkaline sulphates, insoluble in nitric acid. 3. Ammonia does not precipitate baryta, while soda and potash do. 4. Yellow pru iate gives no precipitate. 5. The soluble salts of baryta are poisonous. 6. B.B. salts of baryta communicate a green tinge to the flame. 7. Sulphate of lime in solution precipitates baryta salts immediately. 8. Chromate of potash precipitates alkaline, and neutral solutions of salts of barium, yellow; insoluble in alkalies and acetic acid; while no precipitate occurs with strontium and lime salts. Hydrous Chloride of B. Spec. grav. 3-049 (Karsten). Commonly colorle tables, referable to the right prismatic system. Taste, pungent and disagreeable; poisonous: not altered in the air, decrepitating on being heated, but not liquefying; by ignition it fuses, but does not decompose. Form . BaCl2HO. The anhydrous chloride, which results from igniting the hydrate, is a white ma , with a sp. grav. of 370 to 4:15. When heated in contact with steam, it gives out chlorohydric acid, and becomes alkaline. Form . BaCl. It may be prepared by di olving the native or artificial carbonate of baryta in chlorohydric acid, and crystallizing. It is principally used for testing and precipitating sulphuric acid in solutions. Carbonate of B. , found native as Witherite . It is used as the source of many baryta salts. It is a dense white powder, falling as a precipitate when a soluble carbonate is added to a solution of baryta salt. It is nearly insoluble in water, but di olves readily in acetic, nitric, hydrochloric, and several other acids. Form . BaOCO2. Nitrate of B. is formed by di olving the carbonate of baryta in very dilute nitric acid, and evaporating and crystallizing. It forms white, translucent octahedra, which are anhydrous. It is soluble in 8 parts of cold and 3 parts of boiling water. It is used principally in the preparation of baryta, for chemical purposes, and for detecting acids in analysis. Form . BaONO. Sulphate of B., Heavy Spar, Barytine, is an orthorhombic mineral. Lustre vitreous, inclining to resinous; sometimes pearly. Streak white, color white; also inclining to yellow, gray, blue, red or brown, dark brown. Transparent to translucent; opaque. Sometimes fetid, when rubbed. Optic-axial plane branchy-diagonal. Sp. grav. 4:44. It occurs in nature amorphous, and artificially in a white powder; 1 part is soluble in 43,000 parts cold water ( Kirwan ); oil of vitriol di olves it by boiling, but it is again precipitated on the addition of water ( Withering ). When heated, it decrepitates from the conversion of hygroscopic water between its plates into steam. B.B. it fuses into an opaque white globule -a temperature of 35° Wedgwood being required. When made into a paste with flour and water, and ignited, it phosphoresces in the dark, from the sulphide formed by heat probably again uniting with oxygen, and becoming sulphate. An Italian shoemaker, named Vincenzo Casciarolo, first observed that the Bologna stone (found at the foot of Mount Paterno), a variety of heavy spar, when ignited, became luminous in the dark (Lemery). Sulphate of barytes is found along with galena in the graywacke formations, and likewise in the coal series, and in the old red sandstone conglomeration. It is used to mix with white lead in painting, but is of no value, as it is transparent, and thus injures the white lead. To render it fit for this purpose, it is ground by millstones, and then by stones and water, into a fine powder. The powder is digested in sulphuric acid in iron pots, with the application of heat to remove iron. The sulphuric acid is washed out by water and decantation, and the powder dried into cakes, like magnesia, over a flue. It is frequently mixed with ochre, chrome-yellow, ., according to the color required. Form . BaOSO. Baryt'ic, a . Relating to baryta. Barytocal'cite, n. ( Min .) A monoclinic mineral. Lustre vitreous, inclining to resinous. Color white, grayish, greenish, or yellowish. Streak white. Transparent-translucent. Fracture uneven. Comp. Carbonate of baryta, 66-3, carbonate of lime, 337 100. It is found in England, in the sub-carboniferous or mountain limestone.