Founded in 1845, Scientific American is unique among the periodicals included on this site because it is the only one that is still in publication today.

During the Civil War, Scientific American referred to itself as "a weekly journal of practical information in art, science, mechanics, chemistry and manufactures." It was published in New York City, and devoted perhaps an eighth of its space to innovations in weaponry and armaments. Although some of the proposals were not developed, they give modern readers an understanding of the technical side of the Union military effort.

Moreover, on occasion it was restricted by what it could say and illustrate for Union security reasons. The article dated March 22, 1862, on "The Ericsson Steam Battery Monitor," shows why.