I4o
CVRRENX Tovrcs.
Cerium Tin Alloys.
R. VOGEL. (Zeits. Anorg. Chem., lxxii,
3 1 9 . ) - - T h e cerium tin alloys were investigated by the method of thermal analysis, combined with microscopic examination, and the equilibrium diagram of the system is given. "]?he metals are miscible in all proportions in the molten state, and form the con> pounds Ce._,Sn, C%Sna, and CeSta, which are highly exothermic and melt at I4oo°C., It65°C., and II35°C. respectively. These alloys are attacked by water, with the evolution of gas, and those containing up to 5o per cent. of tin arc rapidly oxidized on exposure to air; when they contain less than 80 per cent. of tin the3' arc pyrophoric, and emit sparks when scratched. The maxmmm pyrophoric effect is observed with the alloy containing 30 per cent. of tin, which corresponds to the compound C%Sn; and this als,~ exhibits the maximum hardness. The cerium-lead alloys bear a general resemblance to these cerium-tin alloys.
Metallic Strontium. A~xJ:,'. (E~G<. xcii, 238~, z42.)--Metallic strontium can be obtained by fusing pure strontium chloride in a hemispherical iron cathode vessel. This allows a low anode current density and avoids overheating. After applying a current of 125 amperes and 40 volts for seven hours, 7(; grammes of mctal can be removed in small lumps up to 3 grammes in weight. The metal is removed from the mixture by crushing on an iron plate and sifting away the chloride. It contains about 98 per cent. metallic strontium, which is a light metal with a silvery lustre when cut. gradually becoming yellow, and finally white and non-lustrous. It is softer than calcium and can be cut with a knife, ft alloys with iron. Hydrogen and nitrogen combine with the hot metal. Its specific gravity is 2.55 and specific heat o.o742, which corresponds to atomic heat 6. 5. The iron alloy is rather hard and decomposes water: this alloy contains 23 per cent. of strontium. Sulphalium--a New Alloy. :\x~,x. !//Jtg., xcii. 2378, ~5o.) --Valuable qualities are claimed for this alloy. It can be machined and cut with facility, as there is no dragging of the material nor clogging of files, as occurs with pure aluminum. Its melting point is about I2oo°F., slightly higher than that of almninum. It is about 3 per cent. denser than pure aluminum. Castings direct from the mould had a tensile strength of from 17,5oo pounds to 21,7oo pounds per square inch, and an elongation of o.4 to 1.2 per cent. in a length of 4 inches. The elastic limit under compression in specimens 2 inches long and I inch in diameter is about 12,7oo pounds per square inch. Tile fracture is granular and sound. Sulphalium is not affected by sea-water, and is used in large quantities for admiralty work. It is well suited for those parts of mathematical instruments which require stiffness and lightness.