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Daniel Drawbaugh, Earth Battery, Jan.14, 1879.
Credit: Patent Office
First developed in the 1840s to power telegraphs, an earth battery generated electricity by using soil or salt water as an electrolyte to charge electrodes made of two different metals. The year after he filed his patent for an earth battery, Drawbaugh announced that he had invented the Bell telephone, and Edison transmitter back in 1866 or 1867.