PHOTOMICROGRAPHS OF STEEL AND IRON SECTIONS 

 AT HIGH MAGNIFICATION. 



By Sir Robert Hadfield, Bart., D.Sc, D.Met., F.R.S., 

 AND Mr. T. G. Elliot, F.I.C. 



Owing to the importance of the study of Microstructure much 

 attention has been given to this subject since the days when the late 

 Dr. H. C. Sorby, F.R.S., of Sheffield, originated, in 1857, this method 

 of examining structures of various materials, including Iron and Steel. 

 Indeed, one of the most striking features of the progress of Metallurgy 

 in recent years is the great development of the use of microscopical 

 methods of investigation. We submit some photomicros, Figs. 1 and 

 2, Plate A, representing some of the early work of Dr. Sorby at 

 9 magnifications. We also submit as a comparison, and in order to 

 demonstrate the great advance in Metallography, Photomicrographs 

 Figs. 3 to 25 showing later work of the writers of this Paper, in which 

 magnifications are dealt with of 100 and up to no less than 8,000. 



In carrying out this work, our best thanks are due to Mr. H. 

 Wrighton, B.Met. for the assistance he has rendered and for the care 

 and skill he has exercised in preparing the Photomicrographs accom- 

 panying our Paper. 



One of us well remembers his conversations with Dr. Sorby 

 regarding the micro study of his own early specimens of 

 Manganese Steel, in 1883-1887. Dr. Sorby never turned away the 

 youngest enquirer, and he little imagined when first describing his 

 method in 1857 what an important aid this would eventually prove to 

 Metallurgy. This is another instance of the great value to the Metallur- 

 gist of original work by the pure Scientist. Next to Sorby, this 

 important branch of investigation owes more for its development to 

 Arnold and Osmond than any others. It has been further advanced 

 by Sauveur, Stead, Le Chatelier, Carpenter, Howe, Martens, 

 Robin, Rosenhain, and many others. 



Sorby bequeathed £15,000 to the Royal Society for the establish- 

 ment of a Fellowship for the carrying on of original Scientific Research, 

 the object specified being " to promote the discovery of new facts 

 rather than the teaching of what is known," and stated that as 

 far as possible the Researches should be carried out at the University 

 of his own native City, Sheffield. To this Englishman, Sorby, the 

 whole world has fully and freely given the credit of originating this 

 important form of research which enables the structure of Iron and 



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