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The excavations in Rome being eonducted on the Palatine Hill have shown a curious and interesting circumstance. The Necropolis has been found to contain remains of the ninth, eighth, sixth, and fourth centuries before Christ. All fragments of the seventh and fifth centuries are lacking and archeologists are engaged in a close study of the field in order to find the reason. A new compound of tantalum has been prepared by C. Chabrie, of Paris. The chloride of tantalum TaCl, is the only one which has yet been prepared, but it seemed likely that others existed, seeing that several inferior oxides of tantalum are now obtained. The author prepares a sub-chloride corresponding to the lower oxide Ta2O2 by reacting with the above-mentioned chloride upon sodium amalgam taken as a reducing agent. He places in a Jena glass tube a mixture of pentachloride of tantalum and a three per cent sodium amalgam. This mixture heats up spontaneously. It is brought gradually to a red heat after a vacuum is made in the tube. Cooling the mass in vacuo, we pour the contents of the tube into a capsule containing acidulated water, then filter and concentrate rapidly under pressure so as to avoid overheating. The solution, which has at first a dark green color, becomes lighter and deposits a green crystalline powder, and this is dried and examined. When seen under the microscope, the powder shows hexagonal crystals of a fine emerald green. Analysis shows the new body to have the formula TaCl2, 2H,O. This compound is soluble in water when freshly prepared; it is but slightly soluble, however, and more so in hot solution. When left in the air the solid product is changed to a brown body, while keeping its crystalline form. Heated in air upon platinum foil it decomposes at a red heat with incandescence, giving off chlorine and leaving tantalic anhydride. The green crystalline body treated with nitric acid does not give tantalic acid, but a reddish brown powder which seems to be formed by an oxidation coming between the tantalic anhydride and the suboxide above mentioned. Nitric acid or bromine water transforms the green solution into a red liquid which tin chloride restores to the green color. Up to the present, but a single combination of silicon and tungsten has been made. The two elements, heated in the electric furnace, give a compound of metallic appearance which is crystalline and hard enough to scratch the ruby. It corresponds to the formula Si,Tu, M. Ed. Defacqz now succeeds in forming a new silicate of tungsten having the formula Si3Tu. It is prepared by two different methods. In the first, silicide of copper is heated in the electric furnace with amorphous tungsten prepared by reducing tungstic anhydride by hydrogen at a red heat. We take 90 parts silicide of copper and 10 per cent of tungsten, heating for one minute with a current of 900 amperes and 50 volts. The metallic mass is then treated by nitric acid and soda, and we finally have a residue of small crystals, which form the new body. The alumino-thermic process can be also used, taking calcined silica 180 parts, tungstic anhydride 45 parts, flowers of sulphur 250, and powdered aluminium 200 parts. After igniting the mass in a crucible and cooling, we have a metallic ingot from which the new compound can be separated. As regards its properties, the silicide of tungsten appears in J.he form of fine prismatic needles, which are very brilliant and of a light gray color. Its density is 9.4 at the freezing point. It is non-magnetic. Chlorine attacks it easily at about 450 deg. C. forming chloride of silicon and hexachloride of tungsten. When heated in air to 900 deg. C. it is not changed. Copper decomposes it at 1,200 deg., forming silicide of copper and also tungsten. Gaseous hydrochloric acid has no action upon it at a red heat, nor most of the other acids. A mixture of hydrofluoric and nitric acids attacks it violently, leaving a residue after calcination of tungstic anhydride. Oxidizing mixtures such as alkaline nitrates and chlorates will dissolve it when heated above their fusing point.
