HERMANN VON HELMHOLTZ 



out a firm, although perhaps hidden, basis of truth. 

 We must also in his case acquiesce in the fact, that the 

 greatest benefactors of mankind usually do not obtain 

 a full reward during their lifetime, and that new ideas 

 need the more time for gaining general assent the 

 more really original they are, and the more power they 

 have to change the broad path of human knowledge.' 



The lecture, however, was not merely a panegyric 

 of Faraday. Helmholtz unfolded to the English 

 chemists the theory of electrolysis, in its most 

 modern form, as moulded by the law of the con- 

 servation of energy, and the laws of electrolysis 

 discovered by Faraday himself. Electricity can pass 

 from the fluid to the electrodes only under condi- 

 tions of equivalent chemical decomposition, which is 

 brought about by the electrical forces splitting up 

 the chemical compounds present. Helmholtz proved 

 by calculation that the electric forces are quite 

 sufficient for this work, as shown by the unexpected 

 magnitude of the electrical equivalents that change 

 places during the process. 



As already stated, p. 206, Helmholtz found that all 

 the hypotheses of electrical action, such as those of 

 Weber, the Neumanns, Riemann and others, ex- 

 plained certain of the facts. For example, he found 

 that they all accounted for the phenomena of elec- 

 trical currents in closed circuits, but they did not 

 do so for conductors which end in insulating non- 

 conductors, or what might be called open or 

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