163 REPORT — 1867. 



mere employment of the eyes and hands of the most experienced puddler. 

 Thus it appears that the Bessemer process enables us to manufacture steel 

 "with any given proportion of carbon, or other eligible element, and thus to 

 describe the compound metal in terms of its chemical constituents. 



Important changes have been made since Mr. Bessemer first announced his 

 new principle of conversion, and the results obtained from various quarters 

 bid fair to establish a new epoch in metaUurgic manipulation, by the pro- 

 duction of a material of much greater general value than that which was pro- 

 duced by the old process, and in most cases of double the strength of ii'on. 



These improvements are not exchisively confined to the Bessemer process, 

 for a great variety of processes are now in operation producing the same 

 results, and hence we have now in the market homogeneous, and every other 

 description of iron, inclusive of steel of such density, ductility, &c., as to meet 

 all the requirements of the varied forms of construction. 



The chemical properties of these diflereut kinds of steel have been satis- 

 factorily established ; but we have no reliable knowledge of the mechanical 

 properties of the ditferent kinds of homogeneous iron and steel that are now 

 being produced. To supply this desideratum, I have endeavoured, by a 

 series of laborious experiments, to determine the comparative values of the 

 different kinds of steel, as regards their powers of resistance to transverse, 

 tensile, and compressive strain. 



These experiments have been instituted not only for those engaged in the 

 constructive arts, but also to enable the engineer to make such selections of 

 the material as will best suit his purpose in any proposed construction. In 

 order to arrive at correct results, I have applied to the first houses for the 

 specimens experimented iipon, and judging from the results of these experi- 

 ments, I venture to hope that new and important data have been obtained, 

 which may safely be relied upon in the selection of the material for the 

 different forms of construction. 



For several years past attempts have been made to substitute steel for 

 iron, on account of its superior tenacity and increased security in the con- 

 struction of boilers, bridges, &c. ; and assuredly there can be no doubt as to 

 the desirability of emplopng a material of the same weight and of double the 

 strength, provided it can at all times be relied upon. Some difficulties, how- 

 ever, exist, and until tlioy are removed it would not be safe to make the 

 transfer from iron to steel. These difficulties may be summed up in a few 

 words, viz. the want of uniformity in the manufacture, in cases of rolled 

 plates and other articles which require perfect resemblance in character, and 

 the uncertainty which pervades its production. Time and close observation 

 of facts in connexion "SNith the different processes wiU, however, surmount 

 these difficulties, and will enable the manufactm-er to produce steel in all 

 its varieties with the same certainty as he formerly attained in the manu- 

 factture of iron. 



In the selection of the different specimens of steel, I have endeavoured to 

 obtain such information about the ores, fuel, and process of manufacture as 

 the parties supplying the specimens were disposed to furnish. To a series of 

 questions, answers were, in most cases, cheerfully given, the particulars of 

 which wiU be found in the Tables. 



I have intimated that the specimens have been submitted to transverse, 

 tensile, and compressive strain, and the summaries of results wiU indicate 

 the uses to which the different specimens may bo applied. Table I. gives 

 for each specimen the modulus of elasticity and the modulus of resistance to 

 impact, together with the deflection for unity of pressui-e ; from these experi- 



