Vo]. 65.] ANNIVERSARY ADDRESS OP THE PRESIDENT. lv 



sometimes more or less completely broken up by violent collision, and the 

 fragments again collected together and solidified. Whilst these changes were 

 taking place, various metallic compounds of iron were so introduced as to 

 indicate that they still existed in space in the state of vapour, and condensed 

 amongst the previously formed particles of the meteorites. At all events, the 

 relative amount of the metallic constituents appears to have increased with 

 the lapse of time, and they often crystallised under conditions differing entirely 

 from those which occurred when mixed metallic and stony materials were 

 metamorphosed, or solidified from . . . fusion. . . .' 



It was in order to explain the origin of meteoric iron that Sorby 

 comrnenced that remarkable series of investigations into artificial 

 irons, which has since developed into a new science — micro- 

 metallography — now proving of such immense importance in its 

 application to the arts. His first work on this subject was com- 

 menced in 1863, and the results were published in the following year. 

 Twenty-two years elapsed before they attracted any attention ; but, 

 after publishing a paper on the application of very high powers to 

 the study of the microscopic structure of steel, which appeared in 

 the Journal of the Iron & Steel Institute for 1866, Sorby was 

 requested by that Institute to continue his work, and Dr. Percy and 

 Sir Henry Bessemer were appointed to act with him in deciding 

 as to the best way of illustrating a complete paper on the subject. 

 Sorby proved that the different kinds of iron and steel are varying 

 mixtures of well-defined substances, and that their structure is 

 in many respects analogous to that of igneous rocks. To one of 

 these constituents the name of Sorbite has been given in his 

 honour. 1 



It is pleasing to reflect that by these researches the descendant 

 of a long line of workers in iron and steel was able to continue the 

 traditions of his family on another plane ; and again, that micro- 

 metallography is now one of the most important means of research 

 employed by the Professor of Metallurgy who holds his chair in 

 that University which Sorby did so much to create. What important 

 practical results may follow from the scientific training given 

 in this University may be gathered from Mr. Haldane'"s address to 

 the British Science Guild on January 18th, 1908, when he spoke of 

 his visit to one of the great Sheffield foundries, where he found 

 among the employees men who had been students in the University, 

 and was informed by one of the heads of the business that Sheffield 

 was all but unique in the training given in this way to its young 



1 Since this is the name of a crystalline principle found in the berries of 

 the mountain-ash, it would be better to alter the spelling to Sorbyite. 



