Guns covering the harbor: Charleston’s inner ring of defenses

Earlier posts have focused on the outer harbor defenses on Morris and Sullivan’s Islands and the approach defenses on James Island.  Those were the outer defenses of Charleston, South Carolina and the most actively engaged.  Behind that, the Confederates built defenses, and in some cases reoriented older fortifications, as a backup.  In March 1863 those defenses lined the throat of Charleston’s harbor.  The main feature in this inner defense was the cross fire formed between various batteries and forts across the South Channel.  Beyond that, several positions covered specific features around the city.

In a September 1862 report, General P.G.T. Beauregard explained why these works were of value to Charleston’s defenders :

… The plan of naval attack apparently best for the enemy would be to dash with as many iron-clads as he can command, say fifteen or twenty, past the batteries and forts, without halting to engage or reduce them. Commodore Ingraham thinks they will make an attack in that way by daylight….

After forcing the passage of the forts and barriers and reaching  the inner harbor gunboats may lay within 600 yards of city face of Fort Sumter exposed to fire of about fifteen guns. The magazines would be unsafe as now situated, or until counter-fort shall have been extended sufficiently along city face….

The threat was that seen since the time men first armed boats – put a warship in the relative calm of a harbor and its guns dominate the shore.  In that report, Beauregard speculated that the defenses, as they existed that September, were not sufficient:

… If iron-clads pass the forts and batteries at the gorge, or throat, of harbor then the guns at Forts Ripley and Johnson and Castle Pinckney would be of no avail to check them. In consequence of the exposed condition of the foundations of Fort Ripley and the general weakness of Castle Pinckney it would not be advisable to diminish the armament of the exterior works to arm them, and this necessarily decides that Fort Johnson cannot be armed at the expense of the works covering throat of harbor. Fort Johnson must be held, however, to prevent the possibility of being carried by the enemy by land attack and the establishment there of breaching batteries against Fort Sumter. The batteries at White Point Garden, Half Moon, and Lawton’s and McLeod’s Batteries for the same reasons cannot be prudently armed at present with heavy guns.

So in addition to all the other work needed at Charleston, and all the other forts wanting for heavy guns, the inner works needed attention.  By March 1863, the established works presented an improvement, at least on the map:


The harbor facing guns from Fort Sumter and Sullivan’s Island offered limited coverage.  But the main works covering the South Channel were Fort Johnson, Battery Glover, Battery Ripley, and Castle Pinckney, with the famous (or infamous) floating battery thrown into the mix.

I discussed Fort Johnson and Battery Glover in context of the James Island defenses.   The armament of Fort Johnson included two 10-inch columbiads, a rifled 32-pdr gun, two 32-pdr smoothbores, and a 10-inch mortar.  Battery Glover contained an 8-inch shell gun, a rifled 32-pdr and three smoothbore 32-pdrs.  One issue with Fort Johnson was the orientation of the guns.  To support the outer line, the guns needed to point east.  But to cover the inner harbor, the guns needed to point north and west.  In March 1863, the heavy guns pointed towards the inner harbor.  Later improvements would add outer works oriented to the east.

Guns of Fort Johnson

By March 1863, Battery Ripley, built on wooden cribs placed upon a shoal in the harbor, mounted a 10-inch columbiad in addition to some smaller weapons.  To further support the battery, Beauregard had debris dropped around the shoal to protect the cribs.  The Confederates also sank pilings across side channels near the battery.

Battery Ripley, in the distant left, seen from Fort Johnson’s wharf

Regarding Castle Pinckney, Beauregard “considered it nearly worthless, capable of exerting but little influence on the defenses of Charleston.”  Prior to upgrades, the old fort contained nine 24-pdr smoothbore guns and one rifled 24-pdr.  Later the fort received 10-inch columbiads.

Interior of Castle Pinckney

I mention the floating battery here, but that defense is somewhat an enigma in relation to the situation in March-April 1863.  Some accounts have it armed with four 8-inch naval guns and have it posted between Fort Johnson and Battery Ripley.  But it may have been destroyed by a storm during the summer of 1863.  Regardless, by the spring of 1863 the battery fell into disfavor and did not factor into plans for defense of Charleston.

The Floating Battery

The works mentioned above lacked the punch of Charleston’s outer defenses.  With most of the heavy guns going to the outer defenses, for good reason, the inner forts could do little against Federal ironclads.  The nightmare scenario that Beauregard feared – the monitors just pushing their way into Charleston harbor – continued to haunt his plans.  So it is little wonder the board assembled that March addressed the deficiency. But as we’ve seen, the Confederates simply lacked the resources – guns, labor, and troops – to do much else.

I’ll continue the walk through Charleston’s defenses with a look at the batteries and fortifications which defended the city itself in the next installment.

(Citations from OR, Series I, Volume 14, Serial 20, pages 622-3.)