252 GREAT MEN OF SCIENCE 



since the derivatives of benzene (the international name of 

 which is benzol) form so important a part of chemistry. 



These years were also signalised by Ampere's important 

 work, which Faraday not only studied with great admiration, 

 but immediately reproduced with his own and extended 

 observations, whereby he exhibited the rotation of magnets 

 about currents and of current-carrying conductors about 

 poles, which is so important for the understanding of these 

 phenomena. Though others had to some extent anticipated 

 him in this matter, these studies nevertheless formed an 

 effective prelude to the great discoveries he was soon to 

 make, inasmuch as he became perfectly familiar with 

 everything known concerning electromagnetism by his own 

 personal observation. 



Faraday was now forty years of age, he was an admired 

 successor of Davy's in the delivery of the Royal Institution 

 lectures, and also director of the laboratory, which thus gave 

 him the most favourable possible circumstances for work. In 

 the autumn of 1831 the discovery of electromagnetic induc- 

 tion occurred. This was an entirely new method of pro- 

 ducing an electric current, at that time foreseen by no one, 

 but which to-day, now carried out on the largest scale, has 

 superseded almost all other methods. It has also made 

 possible the production of very powerful electric currents, 

 such as could never have been made by Volta's methods, 

 and so laid the foundations of the magnificent success of 

 modern electrical engineering. 



The phenomenon could not have been predicted, inas- 

 much as it was not deducible from any known fact, but Fara- 

 day was an investigator who allowed innumerable analogies 

 with the known, of the nearest and most distant description, 

 to arise in his mind, and never became tired of doing this; 

 he never regarded anything as impossible before he had 

 thoroughly tested it, nor did he fail to use every effort to test 

 it in every possible direction. Oersted and Ampere had 



