According to Historical Etna, Spang, Chalfant and Company was originally founded by Henry Spang in 1894 as the Etna Iron Works and later as Spang and Company.

THE IRON-CLAD DUNDERBERG. SURVEY OF THE RE D'ITALIA. Share full article. Jan. 14, 1864. Credit... The New York Times Archives. See the article in its original context from January 14, 1864, Page 2 ...