Perhaps they had gotten so used to their slaves’ presence that they forgot they were there. Or perhaps opinions of slave workers were just so low that they didn’t think it mattered. Maybe it was a mixture of both, but whatever the reason, Southerners had no problem dropping important information in front of their slaves. And those underestimated men and women often became runaways or freed slaves who wasted no time in giving information to the Union about Confederate troop movements, tactics, and orders. These reports were referred to as “black dispatches,” and are considered one of the most significant and productive sources of intelligence used by Union forces during the war.
There are many brave examples of those who provided black dispatches, but one husband and wife duo found an especially creative way to spy for the Union.
The man’s name was Dabney, and he was a runaway slave who had found work as a cook for Joseph Hooker’s camp in Virginia. He had a familiarity with the area around Fredericksburg that made him a valuable asset to the group, and he often advised the troops on the terrain and which routes to take. After a few weeks, Dabney’s wife took a laundress job for a woman in Confederate territory. Not long after her departure, Dabney started providing reports of Confederate troop movements, and these reports proved to be surprisingly accurate. But how? Dabney never left camp or talked to any of the Union scouts. He just seemed to know.
The officers finally asked him to give up the secret, and he led them to a part of the camp from which all of Fredericksburg could be seen…including the house where Dabney’s wife now worked. He revealed that he and his wife had worked out a system of signal communication using her employer’s laundry. Depending on how she hung it on the line, Dabney knew whose troops were moving, which direction, and other useful details that his wife learned from the unsuspecting Confederates around her. For example, a red shirt would represent General “Stonewall” Jackson, and a pair of pants hung upside down meant the troops were headed west.
Dabney continued providing these “black dispatches” to Hooker and his men for the remainder of their time camped in Fredericksburg. Though no official documents exist to back this popular war story, there is most likely some factual basis to the tale. Whether accurate or not, this story has been told time and time again in books and articles about military intelligence, and goes to show not only the extreme aid given to the Union by the freed and runaway slaves, but the creative lengths they went to in order to gain information.
There are a couple of Fold3 pages that go into more detail about those slaves who turned on the Confederacy to aid the Union: Union African Americans in the Civil War (compiled by bgill) and Black Spies of the Civil War (also by bgill). You can also read more about this particular story and others here and here.