MKTALU'IJGY. 



461 



it. although in an ordinary steel foundry tin- pro- 

 portion of scrap was only 25 per cent. 



The results of testing of nickel sled made by 

 Williain Beardmore witli a view to determining its 

 value as a material for structural and shipbuilding 

 purposes, mark it as possessing a higher tensile 

 strength, with greater toughness and ductility 

 than ordinary carl)on steel. Plates of two grades 

 of steel were experimented upon, mild steel (I>. 

 corresponding to ordinary boiler-plate quality, and 

 la of a higher grade (D. 2ii<>i. suitable for such 

 work as the shells of torpedo-boat destroyers, etc., 

 where lightness of section combined with great 

 strength were desired. Bars of mild quality were 

 subjected to fatigue tests, and their behavior under 

 that treatment compared with that of ordinary car- 

 bon steel, nickel-steel bars and rivets, and steel of a 

 quality suitable for engine forgings. The higher 

 grade steel gave a tension strength and an extension 

 considerably surpassing the British Admiralty re- 

 quirements. The loss of strength due to punching 

 was found to be much less than in carbon steel. 

 Kivets made of it were considerably tougher than 

 ordinary rivets. When nicked with a chisel and 

 hard hammer and then broken, the fracture in 

 nickel steel was fibrous and the metal appeared to 

 have torn gradually, while the ordinary carbon- 

 steel rivet broke short. The bend tests from D.-3UO 

 steel did not differ from those of carbon steel, but 

 the results of the bends from the other quality were 

 superior to anything the author had ever seen in 

 carbon steel of the same grade. The experiments 

 with nicked bars proved that nickel steel offers 

 greater resistance to breaking after being nicked 

 than carbon steel, and also the fracture being 

 fibrous indicate that if a fracture were to appear, 

 say in a propeller shaft made of nickel steel, it would 

 not develop so readily as in a shaft forged from car- 

 bon steel. Ingots of nickel steel show less piping 

 and honeycombing than ordinary carbon-steel in- 

 and the metal is more solid when cast. Thus 

 in nickel steel we have a decided gain in tensile, 

 strength without the dangers attendant upon this 

 result when it is obtained by raising the percentage 

 of carbon. In the author's experience nickel steel 

 could be welded as easily and as satisfactorily as car- 

 bon steel, but there is considerable diversity of 

 opinion on the subject. 



A proposition made at the spring meeting of the 

 British Iron and Steel Institute by Baron Hans von 

 Jiiptner von Jonstorff, of Xeuberg. Austria, for the 

 establishment of an international laboratory in 

 Switzerland to furnish standard analyses of irons 

 and steels, was received witli much favor. The 

 author cited several startling instances of discrep- 

 ancies in analyses in evidence of the need of such 

 an establishment. It is contemplated that all the 

 important nations shall nominate directors of the 

 work : but for the purpose of making analyses, paid 

 investigators will be necessary. The estimated cost 

 of the laboratory is 3.000 (or $1. =5.000) a year. 



In experiments made in Brooklyn, X. Y.. on the 

 endurance of steel and cast-iron columns under load 

 at high temperatures, the columns were placed up- 

 right in a furnace supplied from a producer of the 

 ordinary type, and were loaded by hydraulic pres- 

 sure. A test of a built-up steel column showed 

 that when at a red heat it failed to carry more than 

 a small load. Such a column appeared to be re- 

 duced in strength seven eighths when raised to a 

 temperature of 1.200 F. The next experiments 

 were on hollow cast-iron columns having an esti- 

 mated breaking strength of 902.000 pounds. The 

 column when at a red heat failed under a load equal 

 to 84'8 tons. In another experiment a cast-iron 

 column under the same load had a jet of water 

 thrown on it when the pyrometer indicated a tem- 



perature of 675". without showing any si^n* of in- 

 jury. This experiment was repeated at TT'i and 

 1,075 . and finally when the column had reached a 

 light-red heat and was beginning to yield. In no 

 iid the water seem to have any injurious etlect 

 upon the column. 



Aluminum. Aluminum is found by Percy A. 

 Richards to be extremely susceptible to attack by 

 mercury in whatever form that substance may be 

 present: and the author deduces from the fact a 

 warning that the greatest care should be taken to 

 prevent any aluminum apparatus, etc.. from being 

 brought into contact with it or its combinations. 



Studying the alloys of aluminum, M. Henri Gau- 

 tier finds that, while that metal fuses at 025 ('. and 

 antimony at 4:!2 (.'.. an alloy :>f the two metals re- 

 sists a temperature of 1,100 C. The alloy of tin 

 and aluminum falls to powder when left in the air; 

 but when protected against oxidation, as when 

 under a stratum of water free from air, it continues 

 unchanged. 



Boron bronze, or aluminum boron bronze, is pre- 

 pared by the introduction of aluminum containing 

 boron, not as aluminum boride, but with the boron 

 existing as graphite does in cast iron. As described 

 by II. X. Warren, the commercial process consists 

 in heating in a specially constructed oxyhydrogen 

 furnace a mixture of fluorspar and vitrified boric 

 anhydride until the dense fumes of boron fluoride 

 begin to appear. At this stage ingots of aluminum 

 are introduced into the liquid mass. Reduction at 

 once takes place, with the formation of free boron, 

 which dissolves in the aluminum, rendering it crys- 

 talline and somewhat brittle. When the aluminum 

 thus prepared is alloyed with copper to the extent 

 of from 5 to 10 per cent., a bronze is obtained, 

 denser and more durable than ordinary aluminum 

 bron/.e. and free from brittleness. The most im- 

 portant pr< peity of the alloy is the readiness with 

 which it melts and casts, whereas in the manufac- 

 ture of aluminum bronze one of the greatest diffi- 

 culties is in the insuring of a uniform mixture. 



Reviewing the growth of the aluminum industry 

 under the stimulus given it by the employment of 

 the electro-metallurgical methods, a writer in the 

 Journal of the Franklin Institute mentions as two 

 epochs of great advance the beginning of opera- 

 tions of the Cowles electrical-furnace plant in 1886 

 and the application of the Hall electrolytic process 

 in 1889. While in 1883 only 8.} pounds were pro- 

 duced, and only 263 pounds in 1885. the amount 

 rose in 1886 to 8,000 pounds, and in 1887. with the 

 Cowles pr< cess in full operation, to 18.000 pounds. 

 'In 1889, the year of the introduction of the Hall 

 process, the amount was 47,468 pounds : while it 

 rose in 1890 to 61,281 pounds, in 1891 to 150,050 

 pounds, and in 1892 to C59,885 pounds. Five hun- 

 dred and fifty thousand pounds were produced in 

 1894, and the American output for 1895 was esti- 

 mated by the Iron Age at 850.000 pounds, while 

 the production of 1896. in the opinion of that jour- 

 nal, would exceed 2,000,000 pounds, or 6.000 pounds 

 a day. 



The reduction that has taken place since 1856 in 

 the cost of aluminum is represented as follows: 

 Cost in 1S5<> (spring). $90 per pound: in 18515 

 (autumn). *27.50: in 1859. $18.25: in 1862, $11.88; 

 in 1878. 11.88 : in 1886. sl2 : in 1887. 88.25 : in 1888, 

 $5: in l*s!i. s2.13: in ls!'5. 38 cents per pound. 



The Precious Metals. The ores specially 

 adapted to cyanide lixiviation. according to an ar- 

 ticle in the Engineering and Mining Journal, seem 

 to be those of chemically neutral or slightly 

 character, in which the gold occurs in a very fine 

 state of division. Included in these ores are the 

 auriferous ealcites of Mercur. the siliceous ores of 

 Cripple Creek, and many pyrites in which oxida- 



