Alfred Lewis Vail (September 25, 1807, in Morristown, New Jersey – January 18, 1859) was a machinist and inventor. Vail was central, with Samuel F.B. Morse, in developing and commercializing the telegraph between 1837 and 1844. Vail and Morse were the first two telegraph operators on Morse's first experimental line between Washington, DC, and Baltimore, and Vail took charge of building and managing several early telegraph lines between 1845 and 1848. He was also responsible for several technical innovations of Morse's system, particularly the sending key and improved recording registers and relay magnets. Vail left the telegraph industry in 1848 because he believed that the managers of Morse's lines did not fully value his contributions. His last assignment, superintendent of the Washington and New Orleans Telegraph Company, paid him only $900 a year, leading Vail to write to Morse, "I have made up my mind to leave the Telegraph to take care of itself, since it cannot take care of me. I shall, in a few months, leave Washington for New Jersey,...and bid adieu to the subject of the Telegraph for some more profitable business."
Vail's parents were Bethiah Youngs (1778-1847) and Stephen Vail (1780-1864). Vail was born in Morristown, New Jersey, where his father was an entrepreneur and industrialist who built the Speedwell Ironworks into one of the most innovative iron works of its time. Their son and Alfred's brother was George Vail, a noted politician of his time.
Alfred attended public schools before taking a job as a machinist at the iron works. He enrolled in New York University to study theology in 1832, where he was an active and successful student and a member of the Eucleian Society, graduating in 1836. Visiting his alma mater on September 2, 1837, he happened to witness one of Samuel F. B. Morse's early telegraph experiments. He became fascinated by the technology and negotiated an arrangement with Morse to develop the technology at Speedwell at his own expense in return for 25% of the proceeds. Alfred split his share with his brother George Vail. When Morse took on Francis O. J. Smith, a congressman from Maine, as a partner, he reduced the Vails' share to one-eighth. Morse retained patent rights to everything Vail developed.