The "Planter" and description of Smalls' actions were forwarded by Lt. Nickels to his commander, Capt. E.G. Parrott. In addition to its own light guns, "Planter" carried the four loose artillery pieces from Coles Island and the 200 pounds of ammunition. Most valuable, however, were the captain's code book containing the Confederate signals and a map of the mines and torpedoes that had been laid in Charleston's harbor. Smalls' own extensive knowledge of the Charleston region's waterways and military configurations proved highly valuable. Parrott again forwarded the "Planter" to flag officer Du Pont at Port Royal, describing Smalls as very intelligent. Smalls gave detailed information about Charleston's defenses to Du Pont, commander of the blockading fleet. Federal officers were surprised to learn from Smalls that contrary to their calculations, only a few thousand troops remained to protect the area, the rest having been sent to Tennessee and Virginia. They also learned that the Coles Island fortifications on Charleston's southern flank were being abandoned and were without protection. This intelligence allowed Union forces to capture Coles Island and its string of batteries without a fight on May 20, a week after Smalls' escape. The Union would hold the Stono inlet as a base for the remaining three years of the war. Du Pont was impressed, and wrote the following to the Navy secretary in Washington: "Robert, the intelligent slave and pilot of the boat, who performed this bold feat so skillfully, informed me of capture of the Sumter gun, presuming it would be a matter of interest." He "is superior to any who have come into our lines — intelligent as many of them have been."