Telegraph Register

In 1849 Samuel F. B. Morse received U.S. patent #6,420 for an “improvement in electric telegraphs.” This patent model demonstrated a refinement Morse made to his original telegraph register. Rather than using electromagnets and a lever arm to emboss or ink the dots and dashes on the paper tape, this unit took advantage of the ability of some salts to make colored marks on paper in response to an electric current. Morse described several methods in his patent using different types of salts. Never widely adopted, Morse’s refinement was mostly intended as a response to rival Alexander Bain’s chemical telegraph invention three years earlier.

Most telegraph registers are electrically-activated printers that receive Morse code messages. The message travels as a series of electrical pulses through a wire. The pulses energize the register’s electromagnets which move a lever-arm holding a pen or stylus. A clockwork mechanism pulls a strip of paper across the pen or stylus, recording the message. Short pulses draw or emboss a dot, slightly longer pulses a dash. The sequence of dots and dashes represent letters and numbers.

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