Title: American telegraph system, semaphoric as well as magnetic : American semaphore or marine signals, connected with the electro-magnetic telegraph /
Authors: Rogers, Henry J., 1811-1879.; Black, Furman.; O'Reilly, Henry, 1806-1886.
Publisher: s.n.,
Year: 1846
Subjects: Signals and signaling; Telegraph United States; Cipher and telegraph codes Patents United States.; Cipher and telegraph codes Patents.