5Q EEPORT— 1870. 



by its discoverer, Mr. Deacon, for the direct manufacture of bleaching-powder 

 from the (rases issuing directly from the salt-cake furnace. Air is admitted, 

 together with hydrochloric acid gas, and the mixture is passed over red-hot bricks 

 impregnated with copper salt. The oxide of copper acts as by contact and remains 

 unaltered, whilst the chlorine, watery vapour, and excess of air pass at once into 

 the lime-chamber. There are many practical difficulties in working this process 

 on the large scale, some of which have still to be overcome ; but I believe we shall 

 hear from Mr. Deacon that, notwithstanding these drawbacks, he has accomplished 

 his end of making good bleachiug-powder by this process. 



0>i the Alloys of Copper, Tin, Zinc, Lead, and other Metals ivifh Manganese. 

 By J. Fejstwick Alien-, F.G.S. 

 In the year 1826 a spoon, made by Messrs. Zernecke, of Berlin, was analzyed, 

 and the alloy was found to be composed of copper 57-1 per cent., manganese 19'7 

 per cent., zinc 2.3-2 per cent. This analysis is included in a chapter on Kupfer- 

 mangan, by Mi-. .Tohann Tenner, in his " ' Handbuch der Metall-Legirungen,' pub- 

 lished at Oiiedlinburg. Berthier produced a large number of alloys of manganese 

 with various metals, and h.as recorded their principal properties. 



Whilst, therefore, the alloys of copper, zinc, and other metals with manganese 

 have been more or less known to the metallurgist for more than forty years, whilst 

 their valuable physical properties have been fully described, whilst, moreover, 

 manganese in its ores .almost approaclies iron in its abundance and in its value, and 

 yet for years has been suiiered to escape as a waste product from abnost every large 

 alkali-works, we find tlie metallurgist has not succeeded in reducing it to serve 

 widely except when yoked with iron. _ _ 



To produce metallic manganese was not from the first attempted ; and it is with 

 extreme difficulty that even small quantities of this metal can be prepared. 



From the first it was discovered that in using any of the ores of mang.anese, the 

 iron and the silicon completely destroyed the value of the product. Haying ob» 

 tained a comparatively pure oxide of manganese, recovered from the " still liquors," 

 and having mixed this with oxide of copper {not metallic copper), together with 

 wood charcoal, all finely ground and intimately mixed, the charge was put into a 

 plumbago crucible, then heated in an air-furnace at an intense heat from three to 

 four hours. When the pot was taken out, it was found that, still suspended in the 

 charcoal, and not run down to the bottom, there were innumerable fine shots of a 

 bright white metal ; these, being separated by washing and placed again in the 

 crucible and heated, fused into a pill or button covered with a layer of green vitreous 

 slao-. The process was continued until some small ingots were produced ; and on 

 the'se experiments were made as to their malleability and ductility. 



The alloy was found to be very hard and very brittle when hot ; but when cold, 

 although still hard, it rolled with ease, and was highly elastic. The proportions 

 of the alloy were about :— copper 75 per cent., manganese 25 per cent. When the 

 simple alloy had been produced in sufficient quantities, compound alloys with zinc 

 were tried in various proportions ; and these, again, rolled with complete success. 



Certain mixtures of copper, zinc, and manganese possess the advantage over both 

 German silver and yellow metal, that, whereas the one will only roll cold and the 

 other hot, the manganese alloy rolls from hot to cold. 



As a simple &\\oy, in which the proportions of manganese range from 5 to 30 per 

 cent., it is both malleable and ductile, with a tenacity considerably greater than 

 that of copper. . 



With zinc a compound alloy, resembling in some of its qualities German silver, 

 is obtained. 



The alloy of copper and manganese combines with tin, lead, and other metals ; 

 and from these castings are made, and applied as bearings for machinery, and other 

 similar purposes. 



It was not the nature of the metal itself that prevented it being widely used ; it 

 was its cost. The waste of manganese is very considerable, over 10 per cent, re- 

 maining unreduced, and forming a silicate ; the wear .and tear of the plumbago 



