Pan Scales. Pan scales are a widely used type of analogue or digital scale. They are easy to transport and are often used for weighing specimens in the field. They are a sturdy type of scale and will stand up to rough handling.
Morse's first telegraph device, unveiled in 1837, did use a one-wire system, which produced an EKG-like line on tickertape. The dips in the line had to be de-coded into letters and numbers using a dictionary composed by Morse.
In 1843, Morse and Vail received funding from the U.S. Congress to set up and test their telegraph system between Washington, D.C., and Baltimore, Maryland.