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#1 The telegraph, a system of sending messages or information to a distant place, was invented in 1746. It was a big deal because it suggested that it should be possible to harness electricity to build a signaling device that could send messages over great distances incomparably faster than a human messenger could carry them.
#2 In 1617, Famianus Strada, a learned Italian, wrote a book explaining how two needles could be touched with a lodestone and then balanced on separate pivots, and the one turned in a particular direction would cause the other to sympathetically move parallel to it.
#3 The story of the magic needles was based on a germ of truth: there are naturally occurring minerals called lodestones that can be used to magnetize needles and other metallic objects. However, these did not exist in the form described by Strada.
#4 Chappe's telegraph was a series of wooden panels that could be flipped from black to white as the second hand passed over a particular number. The messages were sent over very great distances very quickly, and a telescope was used to observe the panels.
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