John L. Porter (1813 - December 14, 1893), whose father was a shipwright at Portsmouth, Virginia, was born in 1813. He became a U.S. Navy civilian employee during the 1840s and a Naval Constructor in 1859. After resigning from the U.S. Navy in May 1861, he began working for the Confederate States Navy at the Gosport (Norfolk) Navy Yard, at Portsmouth. Wikipedia
The definitive Wikipedia entry for John L. Porter. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/John_L%2e_Porter