471 



MKTAI.M-|!Y. 



the "true aluminum bronzo," and from it the 

 lower bronzes are made by (iilution of 10 per 

 cent bronze with more conper. Tho " 

 par-cent aluminum broniet nave the character- 

 istics that will probably cause them to be most 

 used, especially in bronze wire and for inarin<> 

 work ; and the fact that with proper and easily 

 taken precautions they can be rolled or ham 

 mered at a red heat will add greatly to their 

 value. Aluminum in bronzes lowers the melt- 

 ing point of the oop|Nr at least 100 or 200. 

 The melting point of the 10-per-cent. bronze is 

 iwinewhere in the neighborhood of 1,700 P. 

 This substance is among the hardest of the 

 bronzes, and hardens considerably upon cold 

 ile the hardness can be lowered by 

 annealing at a red heat and plunging into cold 

 water. Aluminum bronze can be worked in a 

 lathe, pvini: chips that cut smooth and loiii; 

 MM.! <lo not clog the tool; it is a remarkably 

 rigid metal under transverse strain; is peculiar- 

 ly safe under compression strain, and much 

 stronger than any of the other bronzes; and 

 has special antifriction qualities. 



w alloy mentioned in the "Journal de 

 niorlogerie" as a substitute for gold consists of 

 94 parts of copper to 6 parts of antimony. The 

 copper is melted, and the antimony is added. 

 The metals haying been sufficiently fused to- 

 gether, magnesium and carbonate of lime are 

 added to increase the density of the material. 

 The product can be drawn, wrought, and soldered 

 like gold, which it resembles on being polished. 

 It preserves its color against the action of ara- 

 inoniacal salts and of nitrous vapors. 



The principal conclusions drawn from the 

 experiments of Herr C. Heusler, of Bonn, on the 

 strength of manganese bronze having different 

 proportions of manganese at varying tempera- 

 tures up to 400" C., are that (a) a bronze with 5 

 to 8 per cent of manganese is most useful for 

 machine parts in which tenacity is of impor- 

 tance; (6) on the addition of manganese to cop- 

 JT the tenacity of the bronze increases with the 

 percentage of manganese up to a certain limit, 

 then decreases, ana with a still further increase 

 of manganese the strength of the bronze again 



The experiments of Prof. Goodman in connec- 

 tion with the work of the British Alloys Re- 

 search Committee have brought out the fact 

 that antifriction alloys must alwavs contain a 

 metal with a high atomic volume. 'There seems, 

 moreover, to be a direct connection between the 

 efficiency of the antifriction alloy and the 

 atomic volume of one of its constituents. 



An alloy of aluminum with tungsten has been 

 recently introduced into the market. It is made 

 ance, Germany, and England. 



>>w Prows***, The process for electroplat- 

 Qf ships' hulls which has been used with success 

 at the Comraunipaw Basin, Jersey City, consists in 

 applying to the sides of the vessel tanks or baths 

 about 5 feet square, scribed out on the edges to 

 conform with the curvature of the ship's sides, 

 firmly braced and shoved in position, and calked 

 "*!* ** **&* till they are water-tight The 

 nrst bath applied by means of these tonks is of 

 strong acid solution, which cleans the iron plates 

 of the vessel's sides and leaves them ready for the 

 next process. The cleaned spot having been 



washed, the bath is next filled with a s<>h; 



f copper and the !. -tri.- cm 



turned MM. Thecyailide solution coinplel. 



perfectly t i Dg of the side <>f th. 



and in addition nets as a s.>rt <>f llux.cau-; 



film of cupper Iie\t t<> lie deposited 



(Irmly adherent. Tin- cyanide solution 

 been drawn off, a solution of sulphate of 

 takes its place. I^argo plates of cop) 



1 in the bath ana are connected wj^^H 



ve pole of the dynamo, while t 

 -attached to the' side of the ship. T: 

 osition of copper begins immediately. 



the process the entire side of 

 within the limitsof the hath is found thoroucJK 

 and evenly coated with copper about 

 thick, with a closely adherent coating i 1 

 not be removed except with a cold chisel, when 

 a part of the iron comes ofT with it. 



Lon of the bath is so arranged that ii 

 tap a little over the edges of the sect 



.vheivhy when the work is fini-- 



opper plated all over, with ; 

 inch thick, without crack, seams, or joint 

 posure of any kind through which galvai 

 tion can set in. 



In C. Hoenfnes's electrolytic 



production of nickel, solutions of ni< ! 



lied from cobalt and other metals more < 



negative than nickel. Then th. 



in a neutral state or acidulated 'by weak a 



small electrolytical conductivity. T 



sis takes place by means of insoluble an. 



1 in a solution of metal or im-iaN m- n- 

 electro-positive than nickel and separated nH 

 the cathodes by a membrane strong 

 resist chemical and mechanical actions, 

 anodes chlorine is produced, which may 1x3 mM 

 use of in any known way. On the cathodes ntalB 

 is deposited ; it is most useful to keep the caw 

 odes in motion. Anodes of zinc may be n 

 other metal more electro-positive than that to be 

 deposited. In the same way cobalt can be nf 

 duced from cobalt solutions, /inc. from s 

 of /inc. lead from solution of lead. : 

 per from their protochloride solutions. 



G. W. Burton has discovered in electric smofr 

 ing, where the ore is of a rebellious charaotB 

 that by placing the proper flux in the *o^^H 

 the metals will separate and run fr 

 according to the different degrees 

 quired to melt them severally. In ' 

 containing lead, copper, gold, and si 1 

 will separate first and be found in t 

 the tank in globules. As the heat increan - 

 silver will follow, then the copper, and t! 

 trold. the rock being finally consumed or i 

 to an ash. Each metal thus separated *^^H 

 found in the bottom of the tank 

 tides of its own kind. Mr. liu: 

 experience has been that the chemical pi- 

 contained in the ore have much t< 

 rapid heating, ami that the n ; 

 ore the less current re^uir 

 hellions substance itself tending to in< 

 create the heat necessary. Remarkable sucoe J5 

 has been achieved in Canada in the treatn. 

 nickel ores by this system. 



The method of silvering mirrors recently pat- 

 ented by Hans Boas, of Kiel, is based ui 

 fact that when one of the heavy metal 



