L 36 ° ] 



XXXVI.— ON THE PHYSICAL PEOPEETIES OF MANGA- 

 NESE STEEL. By W. F. BAEEETT, Professor of 

 Experimental Physics in the Eoyal College of Science 

 for Ireland. 



I [Eead, December 15, 1886.] 



At the British Association meeting in Aberdeen, in 1885, Mr. 

 J. T. Bottomley read a brief note on " A specimen of almost un- 

 magnetisable steel." As the magnetisation of iron was a subject 

 on which I had worked for some time, Mr. Bottomley was good 

 enough to hand over to me this remarkable specimen of steel for 

 further investigation, at the same time giving me the name and 

 address of Messrs. Hadfield & Co., Steel Founders, of Sheffield, the 

 patentees and manufacturers of this steel. 



Upon writing to Messrs. Hadfield, they furnished me with the 

 result of a chemical analysis of their patent steel, which is as 

 follows : — 



Fe. Mn. C. Si. P. S. 



86-68 12-25 0-80 0-15 0-10 0-02 per cent. 



Other varieties of this steel are manufactured, but this is the 

 most generally serviceable. Specimens of this steel were first ex- 

 hibited at the Institute of Mechanical Engineers in London in the 

 early part of 1884, and a Paper describing this material appeared 

 in the Engineer for February 8, 1884. From this Paper I make 

 the following quotation : — 



" It is sufficiently well known that manganese has been employed for 

 many years in the manufacture of steel in various proportions, but any- 

 thing exceeding 1 per cent., it has been generally believed, would render 

 the metal under treatment worthless, and any further addition thereof in 

 excess of this proportion has been considered impracticable. In fact, 

 Dr. Siemens had stated publicly, on many occasions, that the use of 

 manganese was simply a cloak to cover the impurities in steel making, 

 that it covered a multitude of sins : and this was the general opinion of 

 the steel trade. Messrs. Hadfield, of Sheffield, however, engaged in a 

 long series of experiments and tests, with the object of discovering its 



