PREFACE 



IN accepting the invitation of the publishers to write a book of 

 a popular character on modern chemical discovery, I am con 

 scious of undertaking a very serious task. The difficulties to be 

 encountered are twofold ; first, there is the complexity and 

 diversity of the subjects to be dealt with, and, secondly, the 

 difficulty of rendering an account of many of them in language 

 at once intelligible to the non-technical reader and free from 

 serious inaccuracy. The author is indebted for assistance from 

 many friends, and in connection especially with the chapters 

 dealing with manufacturing processes such help was indis- 

 pensable. To all in the following list who have thus kindly 

 given information or supplied illustrations he desires to return 

 his most grateful thanks. 



Professor S. Arrhenius, of Stockholm. 



Professor A. J. Brown, of Birmingham. 



Professor W. A. Bone, of the Imperial College. 



The Council of the Chemical Society. 



Sir William Crookes, President of the Royal Society. 



Lt.-Col. Professor A. W. Crossley. 



Sir James J. Dobbie, Chief Government Chemist. 



C. S. Garland, Esq., of the Volker Lighting Company. 



J. C. Maxwell Garnett, Esq., Principal of the Municipal School 

 of Technology, Manchester. 



The Gas Light and Coke Company. 



R. S. Giles, Esq., of Rangoon. 



Messrs. Hird, Chambers, and Hammond, Chemical Engineers, 

 Huddersfield. 



vii 



asonns 



