124 SUMMARY OF CUEEENT UESEAECHES RELATING TO 



Silver-copper Alloys.* X. Kurnakow, X. Puschin, and X. Senkow- 

 sky have determined the electrical conductivity at 2'> , 50 . and 100° 0. 

 of 10 silver-cupper alloys before and after annealing. Hardness measure- 

 ments, by the Brinell method, confirm the results of the electrical 

 determinations, which indicate that the limits of solid solubility are 

 4 atomic p.c. silver in copper, and 9 atomic p.c. copper in silver. 



Silver-sodium Alloys. t — E. Quercigh, by means of a thermal study 

 of twenty alloys melted in an atmosphere of nitrogen, has found that 

 silver and sodium are miscible in all proportions in the liquid state, that 

 no compound is formed, and that the single eutectic lies close to the 

 sodium end of the equilibrium diagram. The solid solution of sodium 

 in silver has the concentration limits to 13 atomic p.c. sodium. 



Ternary Alloys of Magnesium, Zinc, and Cadmium.J — G. Bruni, 

 C. Sandonnini, and E. Quercigh have investigated by thermal methods 

 the binary systems zinc-cadmium. zinc-MgZn 2 , and cadmium-MgZn 2 . 

 The compound MgZn 2 is the only one occurring in the magnesium-zinc 

 system, and behaves like a simple metal in ternary alloys. Having 

 cleared up the doubtful points in the binary systems, the authors pro- 

 ceeded to study the ternary system, cadmium-zinc-MgZn 2 , as a portion 

 of the complete ternary system. Cooling curves were taken of 109 alloys 

 lying in fifteen vertical sections of the usual triangular diagram ; these 

 sections were parallel to the zinc-magnesium side of the triangle. The 

 ternary system examined has three binary eutectic lines meeting in a 

 ternary eutectic point at 250° C. and 73 atomic p.c. cadmium, 25 zinc, 

 2 magnesium. 



Alloys of Copper, Antimony, and Bismuth. §— X. Parravano and 

 E. Yiviani, first investigating the binary systems, find that antimony 

 and bismuth appear to form a continuous series of solid solutions. 

 Antimony does not retain copper in solid solution, and copper does not 

 retain more than a minute quantity of antimony in solid solution. The 

 compound Cu 3 Sb melts without decomposition ; the ternary system is 

 therefore regarded as two systems, Cu-Cu 3 Sb-Bi and Cu 3 Sb-Sb-Bi. The 

 compound Cu 3 Sb and bismuth are only partly miscible in the liquid 

 state, and they do not form compounds or solid solutions. The general 

 form of the equilibrium diagram of the ternary system Cu 3 Sb-Sb-Bi is 

 discussed. 



Heat-treatment of Bronze. || — E. Heyn and O. Bauer have inves- 

 tigated the unsatisfactory behaviour of some bronze bushes containing 

 98 p.c. copper and 7 p.c. tin, which were shown by hardness measurements 

 to be softer than good specimens having the same composition. Micro- 

 scopical examination revealed that the hard samples contained two con- 

 stituents, the soft samples only one. Heat-treatment experiments showed 

 that the soft condition and its corresponding structure were produced by 



* Zeitschr. Anorg. Chem., lxviii. (1910) pp. 123-40 (4 figs.). 



t Tom. cit., pp. 301-6 (2 figs.). J Tom. cit., pp. 73-90 (8 figs.). 



§ Atti R. Accad. Lincei, xix. 1 (1910) pp. 835-40 ; xix. 2 (1910) pp. 69-75, 

 through Journ. Chem. Soc, xcviii. (1910) pp. 779, 852. 



|| Mitt. Kgl. Materialpriifungsamt, xxviii. (1910) pp. 344-8, through Journ. Soc. 

 Chem. Ind., xxix. (1910) p. 1110. 



