I will point out one minor error in the "Handbook Article". Morse code was not used during the War between the State. Morse Code wasn't use until the Titanic sinking in 1912. It was adapted to simplify the commonly use and more difficult telegraph code of the time called the American Code.
David O. Dodd learned the American Code while working as a telegrapher for Mr. Snow and Ketchum owners of the Little Rock, Pine Bluff, Princeton, Camden and Arkadelphia Telegraph Company.