USS Signal – a small 190-ton steamship – was acquired during the second year of the American Civil War by the Union Navy and outfitted as a gunboat.

Signal's work for the day steaming up and down shallow, winding streams in hostile territory was a sample of the service she would perform throughout her career.

She and Marmora again ascended the Yazoo on 11 December to obtain information needed for a projected joint Army-Navy expedition in that area to outflank Vicksburg.

On 8 December 1863, Signal and USS Neosho defended disabled merchant steamer Henry Von Phul, which had been shelled by a Southern shore battery.

In the ensuing battle, Signal was disabled and ran aground where she was reluctantly set afire and abandoned by her crew which was captured ashore.

Six of the crew members, Quarter Gunner Charles Asten, Gunner's Mate George Butts, Seaman John Hyland, Seaman Timothy O'Donoghue, Boatswain's Mate Michael McCormick, and Pilot Perry Wilkes, were awarded the Medal of Honor for their conduct during the ship's final engagement on the Red River.