D. CHEMISTRY AND METALLURGY. 55 



ver, and after rinsing shows no trace of red. With Britannia 

 (composed of tin, antimony, and a little copper) a black spot 

 will be developed, but no effect will be seen with platinum. 

 Upon a surface amalgamated with mercury a reddish-brown 

 deposit will be perceived, which is completely washed away 

 on rinsing. With lead and bismuth a yellow deposit remains. 

 Zinc becomes strongly etched, the liquid, however, disappear- 

 ing completely on rinsing. Tin is attacked also very decided- 

 ly, but the test liquid imparts a brownish color, and an addi- 

 tion of water produces a yellow deposit which readily attach- 

 es itself to the metal. 8 (7, 1870, 411. 



EXTRACTION OF COPPER FROM REFUSE PYRITES. 



The copper-mining industry of Cornwall is said, according 

 to the At/iencqum, to be suffering from a new form of compe- 

 tition. Iron pyrites, it is stated, is now imported in immense 

 quantities from Sweden and Norway for the manufacture of 

 sulphuric acid, and, after the sulphur is extracted, is operated 

 upon for the two per cent, of copper which it contains. About 

 4000 tons of metal were obtained in 1869 from this source, 

 while the entire yield from the native ores the same year was 

 only about 8000 tons. 14 C, CO., 242. 



PHOSPHORUS IX BROXZE. 



An improved method of manufacturing bronze consists in 

 introducing phosphorus in some form during the process of 

 melting the copper, tin, or other metals which form the basis 

 of the compounds, the effect being to very greatly improve 

 the quality as regards elasticity, hardness, and toughness. 

 8 A, January, 1871, No. 6. 



FLUID ALLOY OF SODIUM AXD POTASSIUM. 



It is stated that if 4 parts of sodium are mixed with 2^ of 

 potassium, the alloy will have exactly the appearance and 

 consistency of mercury, remaining liquid at the ordinary tem- 

 perature of the air. 1 A, August 5, 72. 



MALLEABLE BROXZE. 



It is said that, in consequence of the announcements made 

 some months ago before the Academy of Sciences of Paris in 

 reference to the subject of malleable bronze, this substance is 



