On the moonless night of April 16, eleven of Porter's boats drifted silently down toward Vicksburg. Confederate lookouts spotted them and set bonfires on the shore to give light for their artillerists. The fleets poured on steam and rushed downriver amid a cacophony of big guns and exploding shells. Nearly all of the boats got through. They rendezvoused with the troops on the west bank to ferry them across.