B. Morse conceived of an electromagnetic telegraph in 1832 and
constructed an experimental version in 1835. He did not construct
a truly practical system until 1844, when he built a line from
Baltimore to Washington, D.C.
model incorporates basic features of the 1844 receiver. It accompanied
an application for a patent, granted in 1849, in which he described
a method for marking dots and dashes on paper.
years after the first telegraph line opened, 23,000 miles of wire
crisscrossed the country. The invention profoundly affected the
development of the West, made railroad travel safer, and allowed
businessmen to conduct their operations more profitably.