198 ANNUAL OF SCIENTIFIC DISCOVERY. 



various works, imd one hundred and fifty tons of coal are consumed each 

 day. The process employed for manufacturing the steel was discovered 

 after many expensive and laborious experiments by Mr. Krupp, and is kept 

 a profound secret, only a few trustworthy men being allowed to work in the 

 room where the important mixtures are made. The method is said to be 

 founded on the principle of melting together carbonized and decarbonized 

 iron, cast and wrought-iron, and thus obtaining a mixture which has the 

 known composition of steel. 



I was told by a metallurgist at Horde that he had succeeded in obtaining 

 steel in the same way (indeed, it is a process which has long been known to 

 chemists); but all his attempts to make crucibles to stand the heat and 

 action of the materials were unavailing. Others, again, declare that the art 

 lies in the application of a peculiar kind of flux or glass, which protects the 

 smelted metal and allows it to unite properly. Be the process what it may, 

 the results are remarkable. England has sought to compete with this 

 manufactory, but she has always failed. No country has even ap- 

 proached in the size of its production the massive pieces which are turned 

 out here. A mass of ten thousand pounds of cast-steel was sent to the Paris 

 exhibition. The largest shaft of the same material ever made here was, when 

 turned, thirty feet long and ten inches in diameter, and is now in use on a 

 Trench steamer, and cost six thousand dollars; and a single piece of steel 

 has been produced weighing twenty thousand pounds. 



Car axles of steel have been largely manufactured, and Mr. Krupp binds 

 himself to pay a penalty of ten thousand five hundred dollars if any that he 

 sells break within ten years, which, I may say, is throwing the responsibility 

 for this species of railroad accidents upon the right shoulders. Railroad car 

 wheels and bells are sometimes made from steel, but the chief manufacture 

 at present is cannon. These are made from the smallest size up to sixty- 

 eight-pounders, and are cast in a single piece and afterwards bored out. The 

 construction of these guns is remarkable; they consist of a thick, solid cylin- 

 der of steel, made precisely half the thickness of the cast-iron guns (this 

 proportion is assumed arbitrarily, since no experiments have been instituted 

 to prove the proper proportions which should be adopted with this new 

 material), but the metal mass is not heavy enough to withstand the recoil of 

 the powder and-ball, and, consequently, a heavy shell of cast-iron surrounds 

 the breech. The excellence of the guns as warlike instruments is everywhere 

 acknowledged. Correspondence of the United States Railroad Journal. 



-ON TUNGSTEN STEEL. 



It is stated that cast-iron containing from five to six per cent of tungsten 

 acquires an extraordinary hardness. Cast-steel also, containing from four to 

 five per cent of tungsten, will have a tenacity and quality superior to those 

 of the best steels, and will become capable of taking a most extraordinary 

 temper and hardness. According to trials made at Xeustadt, tools of tem- 

 pered tungsten steel were capable of cutting objects made of ordinary cast- 

 steel equally tempered. 



Tungsten has nearly the same specific gravity as gold, and this density is 

 recognizable in the cast-steel alloyed Avith it, by the alteration in the grain of 

 the fractured surface, and by the heightened ring of the steel. In hardness, 

 metallic tungsten nearly approaches the hardest of natural bodies, and it 

 communicates this property to cast-steel, without injuring its tenacity and 



