1870. Ronalds, Francis (1788-1873). A.L.s. to Latimer Clark. Battle, April 11, 1870. 2pp. 181 x 114 mm. Provenance: Latimer Clark. Ronalds invented the first working electric telegraph in 1816. His device involved two synchronized clocks whose dials were marked with the letters of the alphabet; instead of hands, each clock...
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