THE STORY OF NINETEENTH-CENTURY SCIENCE 



Arago, who discovered in 1825 that magnets may be 

 produced at will by electrical induction. But about 

 1830 the scene shifted to London ; for then the protege 

 of Davy, and his successor in the Royal Institution, 

 Michael Faraday, the " man who added to the powers 

 of his intellect all the graces of the human heart." began 

 that series of electrical experiments at the Royal Insti- 

 tution which were destined to attract the dazed atten- 

 tion of the philosophic world, and stamp their originator 

 as " the greatest experimental philosopher the world 

 has ever seen." Nor does the rank of prince of experi- 

 menters do Faraday full justice, for he was far more 

 than a mere experimenter. He had not, perhaps, quite 

 the intuitive insight of Davy, and he utterly lacked the 

 profound mathematical training of Young. None the 

 less was he a man who could dream dreams on occasion, 

 and, as Maxwell has insisted, think in mathematical 

 channels if not with technical symbols. Only his wagon 

 must always traverse earth though hitched to a star. 

 His dreams guided him onward, but ever the hand of 

 experiment kept check over the dreams. 



It was in 1831 that Faraday opened up the field of 

 magneto-electricity. Reversing the experiments of his 

 predecessors, who had found that electric currents may 

 generate magnetism, he showed that magnets have 

 power under certain circumstances to generate electric- 

 ity ; he proved, indeed, the interconvertibility of elec- 

 tricity and magnetism. Then he showed that all bodies 

 are more or less subject to the influence of magnetism, 

 and that even light may be affected by magnetism as to 

 its phenomena of polarization. He satisfied himself 

 completely of the true identity of all the various forms 

 of electricity, and of the convertibility of electricity and 



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