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for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and
Switzerland. The creator and year of publication are essential information and must be provided. See
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invented by Dr. William
Robinson in 1872, from his circular of January 1874. Legend:<br /> C-Primary signal. E-Magnet. H-Line wire circuit. I-Track battery. K-Pri
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C-Primary signal. E-Magnet. H-Line wire circuit. I-Track battery. K-Primary signal battery. L-Distant signal. R-Relay.
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occurred prior to
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invented by Dr. William
Robinson in 1872, from his circular of January 1874. Legend:
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