The Keokuk, named for the industrious town in Iowa, was a cheapjohn copy of a twin-turret ironclad monitor. Keokuk was an experimental vessel built by the U.S. during the Civil War. Designed by C.W. Whitney, a partner of Jon Ericsson's (thus drawing on Ericsson's high credibility), Keokuk was built at Underhill's yard in New York. The ship had an odd whaleback deck, submarine-like underwater shape, and twin screw propulsion. There was an underwater ram bow, visible in the picture made in the yard while building and in the model shot below. Although she resembled a turret vessel superficially, she had in fact far less protection and tactical virtuosity.
Instead of swiveling turrets, she had stationary ironclad gunhouses; inside each, a single pivot gun which could be aimed through any of a three gunports. This was a far more vulnerable construction than the armored turret because the armor was a composite: alternating 2-inch layers of iron and wood, the whole covered with a thin skin of iron plate; the forward gunhouse had a small pilothouse built into the aft side. It was hoped the flimsy wood-and-iron protection would keep out enemy shot nearly as well as the more expensive wrought-iron armor. In hindsight we can see it was folly to suppose that an aggregate 2½" of iron could perform as well as the 8 inches of iron plate that shielded, say, the Monitor's turret, or even the 2½" iron backed by 19½ - 26" of white oak on the Eads ironclads, which their crews found to be insufficient in combat with welll-charged Confederate rifles. The case of the Galena with her lightweight experimental armor shows that the Keokuk's designer was not alone in trying to determine how little armor could be effective in 1862; hard experience in battle would soon show what too little armor meant to the fighting men aboard these experimental ships.
There were other design considerations that should have been cause for concern. The ship's anchors and anchor cranes were extremely exposed at the bow. And rather than simple and straightforward engineering, the vessel was equipped with two highly complex and tempermental engines, making battlefield repairs far more dubious in the event of breakdown.
These caveats were for the future, however; and hopes were high when the ship was launched on December 6, 1862. She commissioned in February 1863, near the apex of the Union's ironclad fever. In all, 76 ironclad ships were ordered by the Federal Government; 42 were commissioned either before, or shortly after, Lee's surrender. During the conflict, Richmond was equally eager to acquire ironclads -- though not nearly so adept at building them. The corresponding numbers in Dixie were 59 ordered and 24 completed.
Keokuk shared most of the disadvantages of the Monitor type: low freeboard, poor visibility, poor ventilation, dubious seaworthiness in anything rougher than a two-foot swell. Her near-submersible lines are apparent in the illustration below, showing the ship at Underhill's just before launch. When complete, the Keokuk carried an armament of two 11" Dahlgren smoothbores, one in each gunhouse. The wooden gunhouse apertures were closed by iron shutters of the scissors type used in the New Ironsides and Galena.
Specifications for the Keokuk:
Dimensions: 159'6" x 36' x 8'6". Displacement: 677 tons. Armament: (2) 11" Dahlgrens in armored, stationary gunhouses. Armor: Alternating layers of 2" iron and 2" oak with 1/2" iron plate as outer skin. Propulsion: Coal-burning boilers; (2) Ericsson VL steam engines shafted to twin screw. Maximum speed: 9 kts. Crew: 92.
Metric specifications:
Dimensions: 48.62m x 11m x 2.6m. Displacement: 677 tons. Armament: (2) 280 mm Dahlgrens in armored, stationary gunhouses. Armor: Alternating layers of 51 mm iron and 51 mm oak, with a 13 mm thickness of iron as outer skin. Propulsion: Ericsson VL steam engines shafted to twin screw. Maximum speed: 16.7 km/hr. Crew: 92.
The Keokuk demonstrated the folly of "going cheap" on armor protection during the siege of Charleston, S.C. Arriving at the Union base at Port Royal, S.C. on March 26, 1863, Keokuk first cleared the channel for the fleet of seven monitors and the ironclad frigate New Ironsides. All was in preparation for a naval attack on the Charleston harbor forts. This was to be a purely naval show -- a fact that marked the faith of the Union navy and Lincoln administration in their new wonder weapon, the ironclad -- for they were to try the strength of a system of up-to-date brick forts, cleverly built with interlocking fields of fire to repel any intruder. The attack commenced at noon on April 7. The channel was quite narrow for such a big fleet, and filled with movable Confederate obstructions -- booms, ropes, pilings, sunken wrecks -- which muddled the Union formation going in to attack. Gunners in Fort Sumter and the Sullivan's Island batteries on the northward shore took full advantage of the Yankees' discomfiture.To find room to maneuver, Keokuk gallantly but foolishly chose to lie close in to Sumter, occupying a patch of water only 600 yards (½ km) from the hot muzzles of its artillery. As shown in this hair-raising illustration by Daniel Dowdey, Keokuk was subjected to a withering fire from the fort for more than half an hour. An estimated 90-plus large-calibre hits progressively knocked her wood-and-iron protection to kindling and repeatedly holed the ship along the waterline. Eventually Keokuk staggered from the fray in a sinking condition. Heroic efforts by her crew kept her afloat overnight, anchored on the shelf off Morris Island, just south of the scene of the fight. With the freshening breeze building up a chop, she foundered where she lay the following morning. (See the map at bottom; the wreck site is charted to right of the arrow marking "Federal Advance.")
And there the wreck remains to this very day: it was recently identified by sonar probe. Keokuk had been in commission for exactly one month. The ship's two Dahlgren guns were salvaged by daring Confederate divers, who battled tricky currents and tides while CSN steamers screened the operation from prying eyes. Once brought to the surface, the Yank artillery was re-mounted in Fort Sumter where it could spew defiance at the blockading fleet at need.
Thus the entirety of Keokuk's career spanned but one month: commissioned Feb. 24, 1863, she was finished by April 8. No other ship in DuPont's squadron was sunk, but many suffered jammed turrets and the Patapsco had an entire section of armor loosened; all suffered loosened bolts and other minor damage in their 30 minutes of combat with the forts. April 7 was a rough day all round for the Union ironclads. Several of the true monitors suffered such damage they had to be withdrawn from service for several weeks. Although casualties were quite low, thanks to their robust armor protection, commanding Adm. DuPont and Secretary Welles had cause to rethink the viability of taking the strong fortifications by naval gunfire alone; the Federal captains were unanimous in their belief it could not be done. Indeed, it would take many assaults and bombardments over a period of years to reduce the proud cradle of secession. Charleston held out against the federal siege until February 17, 1865. By that time ceaseless naval bombardment had reduced much of the town to ashes and subjected its population to harsh privations.
Isometric view showing whaleback form of deck: drawing by Robert MacBride, from Civil War Ironclads (Philadelphia: Chilton Books, 1962).
The order of battle on April 7 immortalized in a contemporaneous illustration from Harper's. The Union ironclads stand up Charleston Harbor to do battle with the forts. Keokuk, last in line, is closest the viewer. Monitors in line are all Passaic class, single-turret boats: from L-R, Nahant, Nantucket, Catskill, [New Ironsides],Patapsco, Montauk, Passaic, and Weehawken.
Relevant Web Resources
- More Pictures of the Keokuk - from U.S. Naval Historical Center
- The First Battle of Charleston Harbor - April 7, 1863
- The Second Battle of Charleston Harbor - Aug. 17 - Sept. 8, 1863
- The Keokuk's Wreck Location - From Wikimapia Satellite Photos
- Charleston After the Surrender - City and Forts Burnt to a Cinder - A Definitive Archive
- US Sloop Housatonic versus Confederate Submarine Hunley - Feb. 17, 1864
- Cast Anchor in the Civil War Home Port
- Top of Page
