John D. M. Stirling, A.D. 1854. "Manufacture of Steel." Cast iron is repeatedly melted with iron oxides containing manganese.

C. A. B. Chenot, A.D. 1854. "Manufacture of Steel, Iron, and different Alloys." Iron ore is roasted, pulverised, and converted into a "sponge." It is then mixed with manganese, and fused.

Auguste E. L. Bellford, A.D. 1854. "Manufacture of Steel and Wrought Iron directly from the Ore." Iron ore is mixed with manganese and other substances, and is roasted. It is then melted in crucibles.

Charles Sanderson, A.D. 1855. "Manufacture of Iron." Sulphate of iron and manganese are added to molten iron.

Abraham Pope, A.D. 1856. "Manufacture of Iron." Iron ore, boghead coke, and oxide of manganese are melted in a reverberatory furnace.

Richard Brooman, A.D. 1856. "Manufacture of Cast Steel." Manganese and other materials are added to wrought iron to make steel.

John D. M. Stirling, A.D. 1856. "Manufacture of Steel." Manganese is used in the manufacture of steel from cast iron and iron ore.

Joseph Gilbert Martien, A.D. 1856. "Manufacture of Iron." Manganese is blown into molten iron.

William Clay, A.D. 1856. "Manufacture of Wrought or Bar Iron." Uses manganese.

Abraham Pope, A.D. 1856. "Manufacture of Steel." Manganese is used in the cementation process.

From the foregoing long list of claimants to the use of manganese in various ways in steel making, it must be evident that a knowledge of its beneficial effect was widely known and highly appreciated nearly a century ago; but the most prominent, and the most practically successful, of all these patentees was a Mr. Josiah Marshall Heath, a civil servant under the Indian Government, who, noticing in the native Wootz steel-making of India the marvellous effect of manganese, conceived the idea of producing steel of superior quality from inferior brands of British iron by its use in the cast-steel process then extensively carried on in Sheffield. Heath came over to this country, and obtained a patent, bearing date the l5th of April, 1839, for the employment of carburet of manganese (that is, manganese in the metallic state) in the manufacture of cast steel: an invention of very great utility, as by its use cast steel of excellent quality could be produced from British iron that had been smelted with mineral fuel. Such steel possessed the property of welding either to itself or to malleable iron. The Sheffield cutlers were thus enabled to weld iron tangs on to the cast-steel blades of table-knives, and also to weld many other similar articles: a process which was not successfully carried on previous to the use of metallic, or carburet of, manganese under Heath's patent.

Mr. Heath, in his specification, does not confine his claim to the use of carburet of manganese in crucible steel melting, but distinctly claims "the use of carburet of manganese in any process whereby iron is converted into cast steel." All that Heath claimed lapsed and became public property when his patent expired, and the right to use carburet of manganese "in any process whereby iron is converted into cast steel" became common property by this publication, even if the patent were invalid. Heath was fully justified in making this general claim, because the results obtained depended on an inevitable chemical law, viz.: whenever metallic manganese, with its powerful affinity for oxygen, is put into molten iron containing disseminated or occluded oxygen, a union of the oxygen and the manganese follows as an inevitable consequence of their strong affinity for each other, wholly irrespective of the process employed in the manufacture of the iron or steel so treated.

In consequence of this successful invention of Heath's, no British iron that has been smelted with mineral fuel is ever made into cast steel in Sheffield without the employment of carburet of manganese. In the