200 ANNUAL OF SCIENTIFIC DISCOVERY. 







and 1 part fine iron-filings, C. Preiss (" Fogg. Annalen") has suc- 

 ceeded in forming a double sulphide of potassium and iron which 

 crystallizes in red needles, has a metallic lustre, and resembles in 

 appearance permanganate of potassium. Its formula is KS,Fe 2 S 3 . 

 The same compound has been obtained independently by 

 R. Schneider, who also has formed by the replacement of iron with 

 bismuth an analogous compound, the formula of which is 

 KS,Bi 2 S3. Chemical News. 



Preservation of Thallium. According to Dr. Bottger, thallium 

 may be best preserved from oxidation by being kept under pure 

 distilled water, freed from air by long boiling, and cooled in a 

 closed flask. A specimen thus treated has preserved its silvery 

 metallic lustre unaltered for three years. Dinglefs Polyteckn. 

 Jour. 



Alloys of Manganese. At the Liverpool meeting of the British 

 Association, Mr. J. Fenwick Allen displayed a series of alloys of 

 manganese with various other metals. They were prepared by 

 first forming an alloy of copper and manganese by the reduction 

 of a mixture of carbonate of manganese and oxide of copper, and 

 producing, from this simple alloy, compound alloys with other 

 metals. The series of specimens was as follows : (1) Manga- 

 nese and copper in various proportions, from 35 to 5 per cent, of 

 iron, as ingot, sheet, and wire ; (2) copper, zinc, and manganese, 

 also, in different proportions, and in a variety of applications ; (3) 

 copper, zinc, manganese, and tin as ingots, and as bearings for 

 machinery ; (4) copper, manganese, and tin in several different 

 proportions as bars; (5) copper, manganese, and lead. A sim- 

 ple alloy of copper (75 per cent.) and manganese (25 per cent.) 

 was found to be very hard and very brittle when hot ; but when 

 cold, although still hard, it rolled with ease, and was highly elas- 

 tic. Certain mixtures of copper, zinc, and manganese possess 

 the advantage over both German silver and yellow metal, that 

 whereas the one will roll only cold, and the other only hot, the 

 manganese alloy rolls from hot to cold. The intense heat required 

 to reduce the copper and manganese was furnished by an applica- 

 tion of the Siemens' furnace, and the hope is expressed that these 

 alloys will not play an unimportant part in the manufactures of 

 the day. 



Iron and Hydrogen. Dr. Klein states that the iron obtained by 

 electrolysis is not, as has often been thought, pure iron, but a 

 compound or mixture of iron and hydrogen, which, when heated 

 to redness, gives off an enormous amount of hydrogen, and be- 

 comes, while greatly increasing in bulk, a silver-white, very mal- 

 leable metal, decomposing water readily at a temperature below 

 its boiling-point, and oxidizing with great rapidity. Les Mondes. 



Peruvian Bismuth. This article now in commerce contains, 

 according to Barth (" Fogg. Annalen ") : 



Bismuth. 93.372 



Antimony (trace of tin), 4.570 



Copper (little iron), 2.058 



100.000 



