METALLURGY, (ALLOVB.) 



high quality and for special purjwsvs an- re- 

 quired. The discovery of Messrs. Kimon- is the 



automatic production Of finished articles dm-, t 

 during I In- process <if electro-deposition. Thedi-- 

 tinguisliing IVnl ures nr i his process an- 1 In- purely 

 automatic character of tin- working, the appar- 

 ently low cost of production, and the greatly im- 

 pro\ed character of tin- finished product. One 

 clcmi-nt of MS \-ilue lies in the fact that the tulx-s 

 produced liy it an- seamless, of a true circular sec- 

 lion of uniform thickness, and homogeneous, and 

 that they can lie produced practically in any 

 length and of any diameter. 



The solvent action of acid ferric Baits is utilized 

 in Herr H. Schultze's process* for recovering 

 tin from tin-plate scrap. The process includes 

 three principal operations the solution of the, 

 tin. its precipitation, and the treatment of tlio 

 waste liquor. When acid ferric sulphate is used, 

 the tin-plate cuttings are placed in iron baskets 

 and lowered into the solution contained in an 

 open wooden vat. The tin covering is stripped 

 oir the iron in a few hours. A similar procedure 

 i> taken when an acid stannic solution is used. 

 The precipitation of the tin from the neutral 

 Mutinous solution is effected by running it into 

 vats containing clean metallic iron. The re- 

 action is slow, but the reduction is complete. 

 The precipitate, when washed and cleaned from 

 iron, is either melted or used for making tin 

 salts. The green vitriol liquors from the pre- 

 cipitating vats are concentrated by allowing 

 them to drop slowly over a large heap of cleaned 

 iron scrap, which causes a rapid evaporation 

 and a deposit of ferrous sulphate on the metal. 

 This may be washed off and purified as commer- 

 cial copperas by recrystallizing, or it may be 

 used for forming the acid liquor for dissolving 

 fresh quantities of tin. 



In the analysis of tin ores, Dr. J. S. C. Willis 

 has found nascent hydrogen the most convenient 

 reagent for obtaining tin in the metallic state. 



Alloys. In a long series of investigations, W. 

 Spring has shown that alloys may be formed at 

 the ordinary temperature, provided that minute 

 particlesof the constituentelements are submitted 

 to great pressure. W. Ilallock has recently given 

 strong evidence in favor of the view that an alloy 

 can be produced from its constituent metals with 

 but slight pressure, if the temperature to which 

 the mass is submitted he above the melting point 

 of the alloy, even though it be far below the melt- 

 ing point of the more easily fusible constituent. 

 A further instance is thus afforded of the fact 

 that a variation of either temperature or pressure 

 will effect the union of solids. 



One thing, says Mr. F. Lynwood Garrison, in 

 his review of the subject, Bnut not be overlooked 

 in considering alloys of steel that, whereas fre- 

 quently admirable results are obtained, in some 

 respects the material is practically worthless on 

 account of, its unworkability in the ordinary 

 operations of the machine shop. This is illus- 

 l rated in some of the grades of manganese steel. 

 One of the most serious disadvantages connected 

 with the use of mild steel tor ship-building pur- 

 poses is its greater liability to corrode in salt water 

 than iron. In several of the new steel alloys, 

 more particularly in nickel-steel, this defect is 

 overcome. Some of these alloys seem to be par- 

 ticularly well adapted for rivets a fact the im- 



portance of which can not IN- o\en-t i mated when 

 we consider that the limit of Mrt-ngth ' 

 united for ship-luiilding. boilers, and other rivet- 

 ed strut-lures is not so much determined by the 

 quality of the steel that may In- u-eil n- |,y the 

 quality of the met -te-l UM-d in combining plates 

 of high tensile strength. 



Of aluminum, Mr. Harrison believe* that while 

 for some special purposes it may I.e employed in 

 the manulacturc of iron this use can not', with 

 our present knowledge of its properties, be large. 

 It might, however, be larger if the material was 

 less expensive. Of chrome steel, the status is, 

 on the whole, not satisfactory. Other steel alloys 

 coming into use are so mnob better that it seems 

 only to be a question of time when it will drop 

 put. Copper acts much like sulphur in render- 

 ing steel more or less red-short and destroy- 

 ing its welding power. Copper-steel alloys are 

 almost too new to determine for what pa'rticu- 

 lar purposes they would be most useful. It is 

 claimed in the Schneider patents that they are 

 useful for making ordnance, armor plate, rifle 

 barrels and projectiles, and also girders for build- 

 ing purposes and ship plates. In view of the re- 

 markable elastic limit of copper-steel, while it 

 maintains at the same time a considerable elonga- 

 tion, its use may become very extensive in the arts. 

 It has the advantage over aluminum, nickel, and 

 tungsten steels of being cheaper to manufacture. 



Regarding the properties of certain new alloys 

 and their value in engineering applications, Mr. 

 Garrison considers Tobin bronze, which is com- 

 posed chiefly of zinc and copper, with small pro- 

 portions of tin, iron, and lead, as practically a 

 brass, or a sterro or delta metal with the addition 

 of a small amount of lead, which tends to render 

 copper softer and more ductile. According to the 

 inventor's claims, it can be forged and stamped 

 at a red heat as readily as steel. Bolts and nuts 

 can be forged from it by hand or by machinery, 

 when cold drawn. Its increased density and 

 high-elastic limit, and the facility with which it 

 can be upset while hot, adapt it for special pur- 

 poses. In forging it, care should be taken to 

 work it only at a cherry-red heat. 



Three copper alloys containing phosphorus 

 have gained a place in engineering work phos- 

 phor-bronze, deoxidized bronze, and the Eureka 

 tempered copper. The use of phosphor-bronze 

 is the result of the discovery, by Messrs. Monte- 

 fiore and Kunzel, that, by adding small propor- 

 tions of phosphorus or phosphnret of tin or cop- 

 per to copper, the oxides of that metal, nearly al- 

 ways present as an impurity, were deoxidized to 

 a greater or less extent, and the copper was much 

 improved in strength and ductility ; the grain of 

 the fracture became firm, the color brighter, and 

 a greater fluidity was attained. The results of 

 comparative experiments with phosphor-bronze 

 and other similar alloys indicate that copper 

 wears nearly 50 per cent, faster than standard 

 phosphor-bronze ; that arsenic bronze contain- 

 ing no lead wears about 42 per cent, faster, 

 but that containing 7 per cent, of lead wears 

 15 per cent, faster, while that containing the 

 same amount of lead as phosphor-bronze wears 

 only 1 per cent, faster; that Damascus bronze, 

 containing as high as 12-50 percent of lead, wears 

 from 7 to 8 per cent, slower: and that an ex- 

 perimental alloy containing less tin and more 



