Page:Collier's New Encyclopedia v. 04.djvu/293

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GALLIPOLI 249 GALLIWASP GALLIPOLI (gal-lep'6-le), a town of southern Italy, built on a steep insulated rock in the Gulf of Taranto, connected with the mainland by a bridge, and 59 miles by rail S. of Brindisi. The harbor is protected by a mole and fortified. The town contains a handsome cathedral and is remarkable for its oil tanks, excavated in the solid rock, in which olive oil is deposited for exportation. Pop. about 12,000. GALLIPOLI, a seaport of Turkey, on the peninsula of the same name (the an- cient Thracian Chersonesus), at the N. E. extremity of the Dardanelles, 90 miles S. of Adrianople, and 130 W. S. W. of Constantinople. The ancient Kallipolis, of which some ruins remain, it was formerly the most important commercial town on the Hellespont, and still retains considerable trade. There are two har- bors, extensive bazaars, and some manu- factures. Gallipoli is the headquarters of the Turkish fleet and the seat of a Greek bishop, and contains numerous mosques and fountains. The town was taken by the Turks in 1356, and formed their earliest European possession ; and here the allies disembarked during the Crimean War. Pop. about 30,000. The "northern portion of the peninsula was the scene of intense fighting in 1915. See World War; Turkey. GALLIPOLI, PENINSULA OF, a tongue of land separating the Hellespont from the ^gean Sea and the Gulf of Saros, 62 miles long, by a varying breadth of from 4 to 12 miles. Lat. be- tween 40° 3' and 40° 38' N., Ion. between 26° 10' and 27° E. GALLIPOLIS, a city of Ohio, the county-seat of Gallia co. It is on the Ohio river, and on the Hocking Valley and the Kanawha and Michigan rail- roads. It is the center of important coal fields, the greater part of which have not been developed. Its industries include iron and wood working estab- lishments, the manufacture of stoves, flour, ice, brooms, lumber, leather, etc. It is the seat of the Ohio Hospital for Epileptics, and has a public library, a park, and Gallia Academy. Pop. (1910) 5,560; (1920) 6,070. GALLIUM, a metallic element, symbol Ga, atomic weight 69.9. Gallium is a triad element. Specific heat 0.079. It was discovered by a French chemist, Lecoq de Boisbaudram, in zinc blende. The metal is obtained by dissolving the blende in sulphuric acid and placing in the solution plates of zinc till the dis- engagement of hydrogen becomes slow, but is still perceptible, by which means the greater portion of the copper, lead. cadmium, iridium, thallium, silver, mer- cury, selenium, arsenic, etc., contained in the ore is precipitated; the clear filtered liquid is then heated with a large excess of zinc, the resulting gelatinous precipi- tate, consisting chiefly of alumina, basic salts of zinc, and gallium, is redissolved in hydrochloric acid, and again heated with zinc, which gives a precipitate in which the gallium is more concentrated. This precipitate is redissolved in hydro- chloric acid, the solution is treated with hydrogen sulphide, and the filtered liquid, after expulsion of the H^S, is fraction- ally precipitated with ammonium car- bonate till the solution of the resulting precipitate in hydrochloric acid no longer gives any indication of the presence of gallium when examined by the spectro- scope. The precipitates are collected and dissolved in sulphuric acid, and cauti- ously evaporated till the free sulphuric acid is expelled; the residue when cold is digested with water till it is dissolved, the nearly neutral solution is boiled, the basic gallium sulphate is precipitated and filtered while hot, and then dissolved in a small quantity of sulphuric acid, treated with excess of potash till the pre- cipitate is redissolved and then precipi- tated by a stream of CO2. Finally the gallium oxide is redissolved in the small- est quantity of sulphuric acid, the solu- tion mixed with excess of slightly acid ammonium acetate, then H;S gas is passed through the liquid; the filtered acetic solution is diluted with water, and heated to boiling, whereby the greater part of the gallium is precipitated as oxide; this precipitate is filtered off hot, washed with boiling water, and redis- solved in sulphuric acid, and the solution mixed with a slight excess of potash, and filtered, whereby a pure alkaline solution of gallium is obtained. Metallic gallium is obtained by the electrolysis of this al- kaline solution, platinum electrodes being used, and the positive electrode being larger than the negative on which the metallic gallium is precipitated, which is detached by dipping the platinum plate in warm water and bending it backward and forward. Gallium is a silver-white metal, which melts at 30°, but remains liquid for weeks at 0°. Cooled to 15° it crystallizes. Gallium is a hard metal, very slightly malleable, and leaves a bluish-gray trace on paper; when melted it adheres to glass ; it does not tarnish in the air. Its specific gravity is 5.95. It gives a brilliant violet line in the spectrum. GALLIWASP. a small lizard, family Scincida^, found in the West Indies. It is an object of terror to the inhabitants, but is really harmless.