In mid-1861, the Confederates raised and began refitting a 3500-ton frigate, the USS Merrimac, that had been burned to the waterline by the Federals.

News of this caused great worry in Washington and the race was on to build Federal ironclads.

With S. H. Pook of Boston, a naval expert, Bushnell and other officials soon developed plans for their own ironclad for the U.S. Navy, a vessel later known as the Galena.

But Ericsson also had his own plans and a working model of a unique floating battery, a low slung ironclad outfitted with a revolving turret.

Through Bushnell's efforts, the USS Monitor was rapidly completed and went on to fight the refurnibished Merrimac (by then known as the CSS Virginia) at Battle of Hampton Roads, saving the Union fleet of wooden sailing ships.