Engraving by Kohl, showing the Montmartre redoubt during the Siege of Paris in 1871, with a 'magneto-electric machine' providing current for arc lights used in a beacon. British engineer Frederick Hale Holmes (c 1840-1875) found that magneto-electric generators could provide a continuous current able to produce a brilliant electric arc for lighting. 'The Germans in vain tried repeatedly to surprise our forts during the night; the electric light kept good guard'. Illustration from 'Electricity and Magnetism' by Amedee Guillemin (1826-1893), published in London in 1891. The Siege of Paris occured one year into the Franco-Prussian war (1870-1871).
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