Captain Ericsson, the famous Swedish inventor, was constructing on Long Island an ironclad about one-fourth the size of the _Merrimac_, and he was urged to all possible speed in its completion.

He kept his men busy night and day and had it finished a day or two before the completion of the _Merrimac_.
The _Merrimac_ carried ten guns, which fired shells and had a crew of 300 men, under the command of Commodore Franklin Buchanan, a former officer of the United States navy.

Late in the forenoon of March 8, 1862, a column of black smoke rising over the Norfolk Navy Yard gave notice that the _Merrimac_ had started out at last on her mission of destruction and death.

As the enormous craft forged into sight it was seen that she was accompanied by three gunboats ready to give what help they could.
Five Union vessels were awaiting her in Hampton Roads.

They were the steam frigates _Minnesota_ and _Roanoke_ and the sailing frigates _Congress_, _Cumberland_ and _St.Lawrence_, all of which immediately cleared for action.