SIR ROBEET HADFIELD, BART. 15 



the ini.eresting case of the direct reduction of Iron from its Ores, and 

 followed the successive changes by the aid of the Microscope. Roberts- 

 Austen also claims that : '' If to these analytical data observations 

 under the Microscope with a magnification of 300 to 400 diameters be 

 added, it is seen that ordinary Iron is merely a metallic network with a 

 close-grained tissue,with submerged scoriaceous opaline, sometimes sub- 

 crystalline, portions, and with little globules and metallic grains ranged 

 in every direction. Sometimes nests of translucent prismatic and 

 bacillary crystals, with metallic portions adhering, are noticed hidden 

 in the paste. These are the grains of Steel which can be made to 

 •disappear by heating." 



Roberts-Austen thought that Modern Metallography owed some 

 of its development to the use made of it in the Study of Meteoric 

 Irons, also that it is quite possible, as has often happened in the 

 History of Science, that there are several independent origins. 



From 1800 A.D. Onwards. 



It is interesting to note that in 1808, Widmanstatten oxidized a 

 heated specimen and took polished sections of meteoric iron, thus 

 originating what is now termed " Metallography." 



Sorby in 1856 founded Petrography, employing sliced sections in 

 connection with the Microscope for the study of rocks, the structures 

 of which are in some cases analogous to those of metallic alloys. 

 In the year 1864 he made an examination of meteoric iron, 

 also studying various metallurgical products ; while in 1885 he 

 discovered Pearlite When Sorby proposed for the first time 

 to submit a specimen of rail, which had broken and caused an accident, 

 to a microscopic analysis, he was told that it was an insane idea. Sorby 's 

 method has since been invaluable for this very purpose — in fact in 

 this Country and in America and elsewhere tens of thousands of 

 photomicrographs have been prepared in connection with the investiga- 

 tion of broken and other rails. 



Mr. J. Stuart— himself a veteran of some eighty-four years — 

 •of the Clapham Common Optical Works of Messrs. Ross, told 

 nie recently that in the 'seventies of the last Century he had repeated 

 visits from Dr. Sorby, who brought various specimens of Steel for 

 examination under the Microscope. Mr. Wenham, Vice-President 

 of the Royal Microscopical Society and the Inventor of the Binocular 

 Microscope, as well as of other microscopical apparatus, was at that 

 time working w4th Messrs. Ross as their Scientific Adviser. Mr. 

 Wenham was also interested in the study of the structure of steel and 

 had many conversations with the late Dr. Sorby, in fact, constructed 

 for him a high power Binocular which Mr. Stuart believes was the first 

 to be used in connection with the examination of Steel. 



Incidentally it may be useful to refer to the fact that the invention 

 of the Oil Immersion Objective was not, as is often imagined, of foreign 

 origin, but was originated by Mr. AVenham in 1870, that is, six or seven 



