VII. METALLURGY. 669 



2767. Sections of Steel Ingots, one cast in the ordinary 

 way, the other compressed while in a fluid state. 



Sir Joseph Whitworth fy Co., Limited. 



By the ordinary method of manufacture, it is found to be impossible to 

 produce sound ductile steel suitable for constructive purposes, owing to the 

 presence of honey-combed air-cells, which are altogether uncertain in their 

 size and situation, and undiscoverable until laid bare by fracture or sections. 



By compressing the metal while in a fluid state this defect is overcome, and 

 a sound trustworthy material produced. This is shown by the two ingots, one 

 cast in the ordinary way, and the other compressed while fluid. 



2765. Tubes tested with Gunpowder, to show the strength 

 and ductility of Whitworth fluid compressed steel. 



Sir Joseph Whitworth $ Co., Limited. 



These tubes were tested to ascertain the strength and ductility of fluid com- 

 pressed steel, as made for guns, torpedoes, &c. 



The ductility is shown by tbe metal bulging under the strain, instead of 

 flying in pieces. 



2766. Sample Pieces of Metal, used for testing, to ascertain 

 the strength and ductility of metal. 



Sir Joseph Whitworth $ Co., Limited. 



There is no scientific line of demarcation between iron and steel. Sir 

 Joseph Whitworth proposes that such a line should be established, and that 

 the quality of a metal should be represented by two numbers, showing its 

 strength and ductility. 



These test pieces are similar to those in use by Sir Joseph Whitworth in 

 testing his fluid compressed steel, to ascertain the proportions of strength and 

 ductility which is required for different purposes. 



The greater the strength, and the greater the ductility, the higher the 

 quality of the metal. 



2767a. Sample of Iron melted by means of compressed air. 



M. Eiifirjils^ Paris. 



2769. Set of cubical specimens of Coal, Ironstone, Lime- 

 stone, and Cold Blast Iron. Illustrating the exact propor- 

 tions, both in weight and bulk, of the minerals, coal, ironstone, 

 a.nd limestone, consumed in the blast furnaces for the production 

 one cubic inch of cast iron at the Bowling Ironworks. 



The Bowling Iron Company ; Limited. 



The coal is coked and the ironstone calcined preparatory to their intro- 

 duction into the blast furnace. 



2774. Diagram, illustrative of a Westphalian blast furnace of 

 most recent construction, for the use of lecturers on metallurgy. 



Prof. Dr. Durre, Aix- la- Chape lie. 



S566c. Furnace for Melting Platinum, by Deville's 



method, with cover and jets. Johnson, Matthey, and Co. 



Size in which 3,250 ounces troy (about 100 kilos.) is melted in one charge. 



2775a. Saturn Steel. M. Breguet, Paris. 



