There was no formal naval intelligence system established during the American Civil War. While a few examples exist of Northern sympathizers, free Blacks, like Mary Louvestre of Portsmouth, sent messages to various Union commanders about the Confederate ironclad construction effort. These links were unofficial and were generally between one Union officer and an individual. The Union nor the Confederacy needed to rely on such clandestine methods since Northern and Southern newspapers provided ample information, usually in a boastful manner. Each antagonist simply needed to obtain a copy of The New York Times or Mobile Register to gather all they needed to know about ironclad development.
Union intelligence was able to receive valuable knowledge about the construction and impending attack of CSS Virginia. The information appeared to flow back and forth across Hampton Roads. On October 6, 1861, Major General John Ellis Wool, stationed at Fort Monroe as commander of the Union Department of Virginia, wrote to Lieutenant General Winfield Scott: