James Buchanan Eads (1820-1887), an American engineer and inventor, developed ironclad ships during the Civil War and designed the world's first steel-arch bridge.

James B. Eads was born in Lawrenceburg, Ind., on May 23, 1820. His father moved his family often, and James attended various public schools until the age of 13. After 5 years as a dry-goods clerk in St. Louis, he became a purser on a Mississippi River steamboat and a self-taught expert in river navigation and hydrography.

Eads patented a diving bell in 1841 and used it on specially designed craft to salvage wrecked riverboats. After a brief, debt-ridden interval, he returned to salvaging, which proved very lucrative after 1848. He amassed a fortune and lived in semiretirement from 1857 to 1861.

In 1861 President Abraham Lincoln summoned Eads for advice on how to use western rivers for military purposes. Eads proposed a fleet of armor-plated, steam-driven gunboats and contracted to build seven 600-ton...