The earliest advance in technology that enabled communication over long distances was the telegraph. Then there was the telephone later on.
so people could communicate over long distances
People could communicate quickly over long distances.
People could communicate quickly over long distances.
People could communicate quickly over long distances.
People could communicate quickly over long distances.
people could communicate more quickly over long distances.
People could communicate over long distances faster.
the radio was needed for communications (mostly over long distances, while over time people used it for entertainment
Telegraph cables- in use since l858 Cyrus Field the principal engineer involved.
They couldn't have used a phonograph because that was after lincolns time but they could have written letters,
The telegraph was well-established by then, although in war-zones the lines had often been cut.When Sherman was crossing Georgia, he could not report to Lincoln until he reached the coast, when he was able to signal to him via the US Navy.
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