After protracted studies conducted throughout the 1830s by three successive military boards, as well as a foreign inspection-tour — all aimed at upgrading U.S. Artillery practices — it was recommended (among other measures) that a new generation of standardized, American-cast seacoast mortars be created so as to supplant the diverse mixture of pieces scattered about in various arsenals. Prototypes for two new designs in 13- and 10-inch calibers were therefore ordered in the spring of 1839, although the larger 11,500-pound version would not go into immediate production, beyond its initial 13-inch prototype and a 12-inch test-variant.
Only the smaller 5,800-pound, 10-inch model was approved that following year for purchase by the War Department, the final details for actual manufacture of ten such seacoast mortars being finalized and the first orders placed as of 1841: five to be cast at Cyrus Alger’s foundry in South Boston, five more at the “West Point” foundry at Cold Spring, New York. Because of the differing years between the initial approval of this project; the experimentation and finalization of its production-details; and the actual delivery of its first finished pieces, this generation of 10-inch seacoast mortars would become rather confusingly known by a variety of designations — being broadly referred to as both the “Model 1839” and “Pattern of 1840” in early citations (such as the U.S. Army’s Ordnance Manual published in the spring of 1841), while remaining generally classified as “10 inch iron mortars, sea coast, Model 1839” as late as the U.S. Army Regulations for 1863.
Yet for all practical purposes, this weapon had also become more commonly known as the “Model 1841” or “M.1841”, presumably because of the year in which it had actually entered into service. Lt.-Col. George Talcott of the U.S. Ordnance Department would report to Congress in late 1843 how the:
… proportions and forms of garrison and sea-coast artillery have been determined, and the regulations in force are calculated to secure their being fabricated of the proper quality …
so that between October 1, 1842 and June 30, 1843, five new 10-inch seacoast mortars had been received and paid for by his department. A “Model 1844” version would also come to be mentioned in official records shortly thereafter, although it seems as if only the bed of this latter version had been altered from the original design, not any changes made in the configuration of the iron barrel itself.
Eventually, a total of 33 of these 10-inch seacoast mortars would be acquired by the U.S. Artillery throughout the antebellum era, until the Civil War erupted — and in fact, the very opening shot of this conflict would be fired by Confederate Capt. George S. James’s 10-inch seacoast mortar from James Island, South Carolina, soaring through the dark rainy dawn to detonate above Fort Sumter shortly before 4:30 a.m. on April 12, 1861. A few dozen more 10-inch seacoast mortars would be hastily ordered by both sides as hostilities got under way, plus an additional eight in a heftier M.1861 version for the Union forces — although this latter design was quickly discontinued in favor of purchases of the much longer-range, more powerful 13-inch weapons.
M.1841 Seacoast Mortars at Pensacola
These photographs, attributed to J. D. Edwards of New Orleans, show two pre-war Model 1841 10-inch seacoast mortars being installed by Florida state militiamen along the shoreline of Pensacola Bay, ca. February 1861. Doubtless, they had been commandeered from among the ordnance left behind in that harbor’s Federal installations, once its small peacetime U.S. Army contingent under First Lt. Adam J. Slemmer had felt constrained to withdraw across the water into Fort Pickens on Santa Rosa Island, at the mouth of its entrance. The most recent U.S. Army inventory for Fort Barrancas, dated at the beginning of that very same year, had officially recorded its main armament as consisting of: “Thirteen 8-inch Columbiads and howitzers, two 10-inch mortars,” etc.
The first photograph reproduced here shows a side-view of one of these mortars in a freshly-dug emplacement, centered atop its wooden-plank platform behind a protective earthen epaulement, whose slope can be partially glimpsed at right. Note the curved cheeks of its mortar-bed, characteristic of the 1841 Model and unlike the angled cheek-fronts featured on the 1844 version. Two militia cannoneers can be seen posing behind their weapon with handspikes, while another pair demonstrate how these implements were to be thrust beneath the maneuvering-bolts, so as to leverage the mortar into firing-alignment. The gunner stands directly behind the mortar, while — given the throngs of volunteers available in these early months before hostilities had actually commenced — two additional men can be seen carrying a round by its shell-hooks (presumably brought from the pyramid of ammunition visible in the rear). A seventh man holds a swab used to clean out a mortar’s bore, while the elderly gentleman with the distinctive high cheekbones, casually standing on the weapon’s rear transom while leaning on its ear-lug, may quite possibly be Col. William Henry Chase — a retired U.S. Army engineer and wealthy local landowner, who was in command of Pensacola’s 1,700 militiamen until relieved by Confederate Brig. Gen. Braxton Bragg on March 11, 1861.
This second photograph shows another M.1841 10-inch seacoast mortar, likewise dug in quite near to the first emplacement, both being interconnected by a communication trench. A different crew of four volunteer cannoneers are posing around this second piece, their gunner in his proper position at its left-rear, under the supervision of an officer armed with a sword and sash. In the background, Colonel Chase can be recognized again, while the pyramid of shells is once more complete — the sample shell from the first photograph having presumably been restored at its top.
Edwards’s first photograph was published in 1911 on Page 59 of Volume 5: Forts and Artillery, of Francis Trevelyan Miller and Robert S. Lanier’s ten-volume Photographic History of the Civil War; Edwards’s second photograph is held by the State Archives of Florida, image number RC04842.
Seacoast mortars constituted the heaviest category in mid-19th Century U.S. Artillery ordnance, being considerably larger than siege mortars of this same caliber — the former designed so as to provide heavy, long-range defensive fire around a major strategic position such as a harbor or city, thus seldom ever having to be moved very far, while the latter were lighter versions specifically created so as to be hauled overland behind an army during offensive operations, to bombard a fortified stronghold. Consequently, the 10-inch M.1841 seacoast mortar with its 46-inch barrel stood more than twice as tall as contemporary 10-inch siege mortars, could fire twice as far, and at 5,775 pounds weighed three times as much. Seacoast mortars furthermore featured a distinctive lug called an “ear” directly atop their barrels, so as to act as a hoisting-point over their center of gravity, for the gin or winch which would of necessity have to be employed in their transportation and positioning.
10-inch M.1841 Seacoast Mortar
Dimensions & Weights
|Length of barrel||46 inches||9.87 inches||Diameter of shells|
|Diameter of bore||10 inches||1.6 inches (avg.)||Thickness, iron shell-casings|
|Length of bore, except chamber||25 inches||1.75 inches||Fuse-hole diameter|
|Depth of conical-shaped chamber||10 inches||87.5 pounds||Weight of empty shells|
|Distance, muzzle-face to trunnion top||37 inches||5 pounds||Powder-charge, to fill a shell|
|Distance between trunnion rim-bases||27.5 inches||3 pounds||Powder-charge, ordinary service|
|Length of each trunnion||6.5 inches||2 pounds||Powder-charge, to burst the shell|
|Diameter of each trunnion||9 inches||5 ounces||Powder-charge, to blow out the fuse|
|Weight of barrel||5,775 pounds|
|Range with a maximum 10-pound powder charge, at a 45° angle of elevation: 4,250 yards|
Given the limited pre-war production of 10-inch seacoast mortars, it is likely that only a couple, or at most only a few were ever shipped to the U.S. Arsenal at Charleston. Official returns for Fort Moultrie’s peacetime armament during the years 1859-1860 do not even list such a heavy weapon among its allotted inventory, but subsequent writings — such as Gen. Samuel Wylie Crawford’s Genesis of the Civil War or Volume 5 of Gen. Clement A. Evans’s Confederate Military History — clearly cite the presence of a “10-inch seacoast mortar” among its artillery. (Gen. Quincy A. Gillmore’s Engineer and Artillery Operations against the Defenses of Charleston Harbor in 1863 would furthermore state that another unaccounted 10-inch mortar was present at Castle Pinckney as well.) Although certainly never part of Moultrie’s main batteries, it is nonetheless possible that one such piece — which would have been quite difficult to maneuver out from Charleston by boat into an advance firing-position on Sullivan’s Island, during any sudden crisis — may have simply been parked in reserve in the open-air compound known as the U.S. Army Reservation behind the peacetime fort, without being included among Moultrie’s official inventory.
Transportation & Emplacement
If a lone seacoast mortar was indeed stored behind Fort Moultrie, it would likely have been stood upon its muzzle atop wooden planks, with its vent sealed and its one-ton mortar bed off to one side. To move both into a firing-position with a sling cart and assemble them into a weapon, the 1861 U.S. Army Ordnance Manual directed that:
Sea-coast mortars and their beds must be slung separately. The sling-chain is passed through the clevis of the mortar and over the axle-tree, and hooked around the pole at its junction with the axle, the pole having been raised vertically.
The three-ton barrel could then be hoisted up beneath the sling cart or into an iron-framed wagon by a large work-detail, to be slowly hauled overland behind a team of oxen or powerful horses toward a selected site.
An emplacement would meanwhile have to be prepared at this site destined to receive the weapon, being laid out in the general direction in which the mortar was to be aimed (known as its “plane of fire”), and within range of any anticipated targets. To create such a gun-position, a sheltered and firm patch of land would have to be leveled off and excavated down to a depth of about nine inches, in which to lay and tamp down thick wooden sleepers to act as the mortar-platform’s foundation. Usually, the rubble and dirt being shoveled out during this excavation would be wheeled up and simultaneously mounded, so as to help erect a protective redoubt enclosing the front end of this position, known as its epaulement.
The mortar’s square wooden platform would be completed by laying thick planks cross-wise atop these embedded sleepers, the front and rear planks being firmly affixed to its foundation with eye-bolts, so as to prevent any slippage and help retain the platform’s shape against the concussive discharges which would inevitably ensue, once firing commenced.
When the weapon itself arrived at the site, its bed would first be centered atop this platform, before the heavy barrel was carefully winched down so as to be seated on top of it, and tilted at a 45° angle. Once installed, the four-ton mortar could be slewed around on its level planking by the crew alone. In addition, some 400 shells would also have to be delivered and stockpiled nearby, each weighing almost 90 pounds, plus a two-ton powder supply and great deal of other equipment and materiel.
Moreover, during the Union disembarkation and entrenchment on Morris Island, South Carolina, in the third year of the Civil War, to besiege Fort Wagner at the mouth of Charleston Harbor as of mid-July 1863, the engineer Maj. Thomas B. Brooks of the New York Volunteers would complain that such regulation mortar-platforms — laid down with standard 9’ x 5” x 3.5” planks supplied by the U.S. Ordnance Department — quickly “showed evidences of failing, and required important repairs after a few hours’ firing.” Therefore, in order to provide a more durable base, Brooks had substituted triple layers of heavier square timbers and planks of yellow pine, seized from local yards. (He furthermore noted the fact that “the greater the weight of the mortar in proportion to the weight of its shell, the less the injury to the platforms.”)
Crew & Equipment
Although a large work-detail would be required to transport and install a seacoast mortar into a prepared position, only five trained artillerymen would be subsequently needed to operate the weapon itself, once it had been assembled: two cannoneer privates (designated as Numbers 1 and 2) stationed “opposite to the front manoeuvring bolts, and Nos. 3 and 4 opposite to those in the rear” of the piece, all under the direction of a single noncom known as its gunner. This crew had to be equipped with an assortment of specialized instruments and tools, beginning with four handspikes for leveraging the weapon around its platform — which were normally distributed at the four corners of the mortar-bed, two on either side of it “leaning upon the four manœvring bolts, the small ends towards the epaulment, those of the front handspikes even with the front of the cheeks.”
Whenever idle, a wooden tompion was left inserted into the mortar’s bore, so as to prevent any grit or moisture from fouling its chamber and the tiny firing-aperture at its very bottom, known as the “vent.” This tompion would have a ring or knob at its center to draw the plug out of the bore, and from which three bags would normally hang suspended:
- the gunner’s pouch, containing his level, gimlet, vent-punch, and chalk;
- a tube pouch, containing “the priming-wire, friction tubes, and the lanyard, wound in St. Andrew’s cross upon its handle”;
- and a haversack, holding fuses and a pair of sleeves.
A wicker basket would be furthermore placed between the supporting runners or “cheeks” of the mortar, to hold less-fragile accoutrements such as a quadrant; a plummet; pointing-cord; a scraper and wiper; shell-hooks; pointing-hooks; a maul or heavy hammer; as well as a corn broom.
With the mortar resting at the center of its platform, and its gunner and four cannoneers standing at attention around it, an officer would shout the opening command “Take implements!” At these words, the gunner would hasten to the front of the piece and oversee the distribution of:
- the protective arm-sleeves and wiper to cannoneer No. 1,
- the basket and maul to cannoneer No. 2;
- the tube-pouch and broom to cannoneer No. 3;
- and the haversack to cannoneer No. 4.
Opening his own instrument pouch, the gunner would thereupon employ his level “to ascertain the line of metal, which he marks with chalk,” before resuming his post at the left-rear of the mortar. And while the gunner had been thus engaged:
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- cannoneer No. 1 would place the wiper on the pounded stake behind him and (assisted by cannoneer No. 3), pull on his protective sleeves, which were usually made of serge or flannel;
- cannoneer No. 2 would remove the tompion and place it, along with the basket and maul, a yard behind his own station, and lay “the shell-hooks on the ground between himself and the basket”;
- cannoneer No. 3 would lay the broom on the ground behind his post, and equip himself with the tube pouch;
- and cannoneer No. 4 would sling the haversack onto his right shoulder, so as to hang down by his left side.
All four would then remove their handspikes from the maneuvering bolts, and stand at the ready.
At the shouted order “Load!”, the gunner would once again hasten to the front of the muzzle and — mounting a wooden block — reach down into its barrel and use a scraper to clear the bore and chamber of any adhered residues, drawing them out with a spoon, then returning these implements to the basket. In the meantime, cannoneer No. 1 would lay down his handspike so as to mount “upon the right cheek and bolster” of the mortar-bed, in order to use his wiper once the gunner had finished scraping out its bore and chamber, so as to ensure that both were left completely clean. Cannoneer No. 3 (likewise without his handspike) would clear the vent with the priming-wire, sweep the platform if necessary, and resume his post.
Meanwhile, cannoneers No. 2 and 4 would have hurried off to the rear with a single handspike and the shell-hooks, to obtain a powder-filled cartridge and a loaded shell. The former consisted of a stitched bag “made of bombazine or flannel,” which was handed to No. 4 from the service-magazine while the shell-hooks were being inserted into the ears of a 90-pound shell by No. 2, so as to be suspended on the handspike between both men as they carried it back to the piece.
Arriving at their mortar’s muzzle, the shell would be rested on the ground momentarily, while No. 4 handed the cartridge up to the gunner, who would insert it into the bottom of the chamber, to be rammed home by No. 1. Immediately afterward, cannoneers 2 and 3 would mount the mortar-bed’s cheeks in order to together hoist the heavy round off the ground by its handspike and shell-hooks, while No. 4 used his wiper to quickly clean the elevated shell, before it reached the mouth. The gunner and No. 1 would then assist in guiding the shell, as it was gently lowered into the bore. Once set atop the inner chamber, the gunner would remove the handspike, toss the shell-hooks behind Position No. 2, adjust the shell so that its fuse was “in the axis of the piece,” and prepare the firing-fuse.
A mortar was aimed by having had a pair of tall stakes driven into the earth previously atop the crest of its epaulement, about three or four feet apart and in a straight line pointed away from the weapon’s muzzle. The pointing-cord was at that time unwound, and tied to the stake which stood furthest from the piece. Drawing this cord taut until its line grazed the second stake, the opposite end of this cord would then be extended to a shorter third stake, driven into the ground about a yard directly behind the mortar platform. A foot-long piece of wood known as a “pointing-board,” notched at its center and marked with gradients, would also have been laid cross-wise on the ground behind this third stake, so as to record any subsequent adjustments in aim.
According to the 1851 Instruction for Heavy Artillery manual: “In pointing mortars, the elevation is first given and then the direction.” Therefore, cannoneers Nos. 1 and 2 — while facing toward the epaulement — would embar their handspikes “upon the bolster, under and perpendicularly to the piece,” so as to help adjust the elevation of its barrel while the gunner held a quadrant to the left side of the mortar face and directed them in either raising or lowering it, while he fine-tuned the quoin accordingly. The amount of powder loaded into the cartridge, determined the actual range at which the shell was to be fired.
Once the correct elevation had been calibrated, the gunner would return the quadrant into the basket, gather the pointing-cord from where it lay coiled at the foot of the epaulement, and move behind the rear stake so as to stretch this cord tight with his left hand, while suspending the plummet from it with his right. He would then use the cord in directing all four cannoneers in shifting the mortar’s front- or rear-end to left or right with their handspikes, until the target was correctly aligned — for in the words of the manual, it was “evident that when the cord, the plummet, and the line of metal are in the same plane, the mortar is properly directed.”
Once a mortar was loaded and aimed, its gunner would visibly signal to the crew with both hands, while simultaneously shouting: “Ready!” Having issued this warning, he would hasten to coil the pointing-cord back at the base of the epaulement, then take up a vantage-point to windward of the mortar so as “to observe the effect of the [forthcoming] shot.” Cannoneers Nos. 1, 2, and 4 would meanwhile retire upon seeing his signal, to reassemble in a line four yards to the rear of their platform, facing forward with “their handspikes held erect by the right side, the right arm extended naturally.”
Only cannoneer No. 3 would remain beside the piece, preparing a friction tube, then inserting it into the firing-vent. Once finished, he would take the lanyard and draw back “three paces to the rear, in prolongation of the right cheek” of the weapon, leaning away from it while holding:
… the handle of the lanyard with the right hand, the lanyard slightly stretched, the cord passing between the fingers, back of the hand up …
so as to await the final command to fire.
The officer in command would ensure that all was in readiness, then shout the actual order to “Fire!” Immediately following its deafening discharge and the dispersal of smoke, the cannoneers would resume their posts at all four corners of their mortar-bed, and begin the process of clearing the weapon so as to load once more, while the gunner waited off to one side to observe the flight and detonation of the shell. A round fired with the maximum ten pounds of powder allowable in a cartridge for a 10-inch seacoast mortar, at a 45° angle of elevation, would take 36 seconds to travel the 4,250 yards that constituted its effective range — almost two-and-a-half miles.
Mortars were often emplaced together in batteries, although it was recommended that the total concentration not exceed three or four pieces, each weapon being assigned its own individual number so as to minimize any confusion during the heat of action. To fire them off in salvoes, every mortar in a battery had to first be properly loaded and aimed, and only when all crews showed themselves to be ready, would the officer in overall command of the battery shout the general directive to: “Commence firing!” However, this particular order simply meant that all gunners and cannoneers were to retire to the rear of their platform, leaving only cannoneer Number 3 beside each individual piece to pull at its lanyard when given the actual signal to fire.
This would occur when the officer shouted directly at each No. 3 in turn, giving the specific designation for each individual piece as he did so, such as: “Number 1 — fire!”, “Number 2 — fire!”, etc. Common sense dictated that downwind pieces were discharged first, so as not to envelope the other poised cannoneers in clouds of choking, acrid gunsmoke. After every weapon in a battery had been discharged, the shouted order “To your posts!” would ensue, for all the crews to hasten back to their stations and begin clearing, loading, and aiming once more.
10-inch Mortars Against Fort Sumter, April 1861
In addition to the single 10-inch seacoast mortar which had apparently been found on Moultrie’s grounds, after the evacuation of its peacetime U.S. Army garrison across the mile of open water into Fort Sumter in late December 1860, South Carolina’s authorities also managed to procure fifteen more such pieces over the ensuing three-and-a-half months before inaugurating hostilities. By the time that their concentric shelling of Sumter was set to commence in the drizzly dawn of April 12, 1861, there were 27 heavy Confederate guns and sixteen 10-inch mortars distributed around the shorelines of Charleston Harbor, the latter weapons split up among seven different batteries on:
- James Island (near derelict Fort Johnson) under Capt. George S. James:
- East or “Beach” Mortar Battery: two 10-inch mortars
- West or “Hill” Mortar Battery: two 10-inch mortars
- at the northwestern tip of Morris Island:
- Cummings Point Battery: three 10-inch mortars (Lts. C.R. Holmes & Nathaniel Armstrong)
- Trapier Battery: three 10-inch mortars (Capt. J. Gadsden King)
- and at the western end of Sullivan’s Island:
- Mortar Battery No. 1, west of Moultrie: two 10-inch mortars (Capt. James H. Hallonquist)
- Mortar Battery No. 2, east of Moultrie: two 10-inch mortars (Capt. William Butler)
- Mount Pleasant Battery: two 10-inch mortars (Capt. Robert Martin)
The very opening shot of the war was fired by one of Captain James’s 10-inch mortars in the East or Beach Battery, exploding directly above Sumter so as to signal the start of a general bombardment from all guns around the harbor. By that same evening, the Federal engineer Capt. John G. Foster would be noting in his journal (written while under fire within that battered stronghold), how:
The effect of the enemy’s fire upon Fort Sumter during the day was very marked in respect to the vertical fire. This was so well directed and so well sustained, that from the seventeen [sic: sixteen] mortars engaged in firing 10-inch shells, one-half of the shells came within or exploded above the parapet of the fort, and only about ten buried themselves in the soft earth of the parade without exploding. In consequence of this precision of vertical fire, Major Anderson decided not to man the upper tier of guns ...
Most of the Confederate mortars employed during this bombardment were M.1841 versions, although there were some older pieces present as well, as can be seen in the woodcut here above. Based upon a contemporary photograph taken by the Charleston firm of Osborn & Durbec, during a visit to Morris Island a few days after the Union garrison’s surrender, then published many years later on Page 76 of Volume 1 of Battles and Leaders of the Civil War, it recorded the militia cannoneers with their pieces at the Trapier Battery — an emplacement described in one newspaper account as being “composed of massive beams and sand-bags,” originally intended to enclose heavy guns, before being given over to these smaller weapons.
And these Trapier mortars were clearly of the older M.1819 vintage, which had lighter-weight wooden rather than iron cheeks, and thus could feature an additional set of wheels to assist in their maneuvering and aiming. Their range was considerably less than heftier M.1841 models, yet this trio of outdated pieces nevertheless succeeded in firing 170 ten-inch shells at Sumter over the span of 34 hours, compared with 197 from the Cummings Point Battery.
Opening Shot of the Civil War
The first shell actually fired, commencing four years of hostilities, came from what was seemingly an M.1841 10-inch seacoast mortar under the command of Capt. George Sholter James. When the Confederate emissaries Col. James Chesnut, Jr., and Capt. Stephen D. Lee — after a wait which had become prolonged well into the night — at last received U.S. Maj. Robert Anderson’s final refusal to surrender Sumter, they immediately penned a note inside one of that fort’s casemates at 3:20 a.m. on April 12, 1861, advising the Federal commander that the shoreline batteries would open fire one hour later. Then, the delegation (which included Col. A. R. Chisholm and an ex-U.S. Congressman from Virginia, the secessionist firebrand Roger A. Pryor) withdrew from Sumter aboard a private boat rowed by six slave oarsmen.
Rather than proceed all the way back into Charleston to report on this rejection, they paused en route at Fort Johnson at about ten minutes before 4:00 a.m., where Lee went ashore and was directed in the darkness to a house occupied by Captain James. Formerly a First Lieutenant in the 4th U.S. Artillery Regiment, James had resigned his commission as of February 1, 1861, to take up service with his native state. Promoted to Captain, he had supervised the installation of a pair of twin-mortar batteries on James Island, both aimed against Sumter: an advance position known as the East or Beach Battery, another further to its rear called the West or Hill Battery.
Instructed by Lee to prepare to fire off a round once the allotted deadline had elapsed, so as to signal the start of a prearranged bombardment from all around the harbor, James instantly issued orders for his men to stand to their posts, and then accompanied Lee part way back toward the wharf. James also offered the honor of pulling the first lanyard to Pryor, whom he greatly admired; but the latter demurred, replying emotionally in a choked voice that he “could not fire the first gun of the war.”
As the boat pulled back out into the dark harbor waters, James hastened to his forward-most East Battery “situated on the front beach, midway between old Fort Johnson and the Lazaretto Point.” There he ordered both of its 10-inch mortars loaded, while standing off to the right-rear of its right-hand piece with his watch in hand, so as to ensure that the deadline was punctiliously observed. Sometime between 4:25 and 4:30 a.m., he shouted the order for Lt. Henry S. Farley to actually tug the lanyard, discharging the right-hand mortar. Captain Lee, waiting expectantly aboard the emissaries’ boat — which was lying on its oars about one-third the distance between Johnson and Sumter — would record years later:
Captain James was a skillful officer, and the firing of the shell was a success. It burst immediately over the fort, apparently about one hundred feet above.
In this engraving, published more than three decades afterward in the monthly Confederate War Journal Illustrated, James’s battery can be pinpointed by its arching line of fire at the extreme upper-left. The West or Hill Battery of his subordinate, Lt. Wade Hampton Gibbes, is also shown firing from a still greater distance beyond, to its immediate right. In the near-foreground at left, gunsmoke can be seen curling from the heavily-reinforced Iron Battery, while the Trapier Battery is ensconced at center — its three 10-inch mortars invisible behind their sandbagged epaulements. Note the two cannoneers emerging from the Trapier’s adjoining service-magazine at lower right, carrying a 90-pound mortar shell suspended between them on a handspike. And far across the harbor, Fort Moultrie can be glimpsed amid its own smoke-plumes at the upper right-hand side of this engraving, with the unmistakable bulk of the Moultrie House Hotel looming at extreme right.
Dismounted Mortar, Fort Pulaski, April 1862
In this evocative scene captured by the 22-year-old apprentice photographer Timothy H. O’Sullivan, a Confederate 10-inch seacoast mortar can be seen lying on its back on the muddy terreplein within recently-surrendered Fort Pulaski, on Cockspur Island near the mouth of the Savannah River, Georgia, where it had fallen after having been flung backward off its bed by the detonation of a Union shell. The force of this explosion had even left the piece’s thick iron muzzle visibly damaged, and apparently sheered off the quoin-screw from its bed as well.
Pulaski’s 360-man garrison had been subjected to 30 hours of long-range, focused shelling by three-dozen heavy Union artillery-pieces on April 10-11, 1862, a barrage originally intended to batter a breach for an amphibious assault against that strongpoint by several thousand men. However, it had soon become evident during the course of this bombardment, that while smoothbore rounds had little effect on the fort’s seven-and-a-half-foot-thick masonry walls, and the aim of Union 13-inch mortars had proven disappointingly inaccurate, the high-velocity shells being fired by five of their rifled 30-pounder Parrott guns and a pair of James guns quickly smashed such a large gap through Pulaski’s southeast corner, that its defenders had capitulated rather than wait to have its northwestern magazine — now exposed directly behind this breach — inevitably struck as well, with catastrophic consequences.
Siege Mortars on Morris Island, Summer 1863
A week after pushing across from Folly Island onto Morris Island, South Carolina, during a dawn assault on July 10, 1863 — yet then failing next day to carry the Confederate stronghold named Fort Wagner, which guarded this island’s northern tip — Union Brig. Gen. Quincy A. Gillmore reported to Washington how he had decided to establish a line of artillery batteries and gradually wear down Wagner’s defenses, by having sappers dig approach-trenches under his siege guns’ covering-fire. His initial Federal line, known as the First Parallel, featured nineteen heavy pieces in its advance position named Battery Reynolds, with a support battery of another thirteen to its left-rear known as Battery Hays, and another battery of four 10-inch siege mortars to Reynolds’ right-rear named Battery Weed.
A half-dozen more Union parallels would be added over the ensuing month, as their siege-trenches edged ever closer up the coast toward Wagner, with guns and mortars being moved up in support. By mid-August 1863, Battery Weed had been left behind as one of the rear-most positions, its five 10-inch siege mortars now manned by the 7th Connecticut Volunteer Infantry under Capt. B. F. Skinner. It is believed that it was around this particular time, that the unit was photographed by Haas and Peale — posed in the act of loading and preparing to fire their smaller 10-inch siege mortars, as can be seen in the accompanying video. The negative (with reproduction number LC-DIG-cwpb-04725) is identified as “Battery Reynolds” in the Library of Congress inventory, yet Reynolds was actually the higher gun-position which can be seen rearing up a few-dozen yards farther in advance of Battery Weed, at the left-hand side of this picture.
10-inch Seacoast Mortars, Battery Kirby, August 1863
Numerous other mortar-positions had also been created in the wake of the Union army’s disembarkation and entrenchment on Morris Island, South Carolina, in anticipation of its slow advance upon Fort Wagner. The journal of the engineer Major Brooks of the New York Volunteers noted on July 15, 1863, how the position furthest inland from the sea was being commenced on that date, far out on:
... the left wing of Battery O’Rorke, afterward called Battery Kirby. Emplacements and a bomb-proof service magazine were prepared for four 10-inch siege mortars. Only one was mounted until after the 18th instant [i.e., July 1863], when two 10-inch seacoast mortars were added; these were used against Fort Sumter in the first bombardment [initiated on August 17, 1863].
Yet since the range of 4,550 yards to Sumter lay well beyond the normal reach of such weapons, Battery Kirby’s cannoneers (a detachment of the 11th Maine Volunteer Infantry under German-born Lt. Charles Sellmer) had to compensate by resorting to firing rounds only sporadically, using cartridges overloaded with two extra pounds of powder — and moreover refraining until there was a noticeable tailwind. Otherwise, they would hold fire until the wind had shifted around into a more helpful direction toward their intended target.
This pair of 10-inch seacoast mortars was apparently photographed in late August 1863, by Haas and Peale. Albumen prints published for sale during that era misidentified these guns as “8-inch Seacoast Mortars,” while even the caption for the single copy held today by the Library of Congress [reproduction number LC-DIG-ppmsca-32448] refers to them as “trench mortars” — a misapplied term, “trench mortar” being a designation which did not gain widespread currency until the First World War, and was then only used to describe much smaller, portable weapons.
Emplacing Union Mortars, Virginia, July 1864
This photograph shows a work-detail preparing to install two 10-inch M.1844 mortars near “Butler’s Crow’s Nest”, opposite Dutch Gap on the James River in Virginia, during the summer of 1864. The initial northwestward push from the fishing village of Bermuda Hundred toward the Confederate capital of Richmond in May 1864 by Maj.-Gen. Benjamin Butler’s 33,000-man “Army of the James”, had been foiled by 18,000 defenders under Gen. P.G.T. Beauregard. A second attempt made by Butler that following month to reach the vital railway-hub at Petersburg, had also ended in failure by June 9th, after which further ill-coordinated assaults by Maj.-Gens. Winfield S. Hancock and George G. Meade had endured heavy casualties, for little gain. With President Lincoln beginning his re-election campaign amid the mounting public outcry in the North against such fruitless losses, the Union armies suspended their offensive operations in favor of digging in where they had become stalled, and instituting a protracted siege of Petersburg.
As part of these overall entrenchments, a dispatch was directed on July 5, 1864 from Col. Henry Abbot of the 1st Connecticut Heavy Artillery, instructing Capt. Alfred Mordecai, Jr., to prepare a battery near “Butler’s Crow’s Nest” to receive a Sawyer gun and a 100-pounder Parrott. Later that same day, Mordecai replied that two 10-inch mortars were also ready for mounting, apparently referring to these pieces pictured here [Official Records, Series I, Vol. 40, Part III, Serial 82, pp. 23-24]. Once their emplacements had become cleared and leveled off, the epaulements would be completed and wooden platforms embedded firmly into the soil so as to receive the mortar beds, to be followed by the winching down and seating of the mortar-barrels themselves. Note how the bed at the center of this picture is temporarily resting atop a sleeper, so as to make it easier to raise and reposition later.
Captured Mortar at Fort McAllister, Georgia, December 1864
Originally an earth- and log-fortification on the southern bank of the Ogeechee River, this fort had been erected to deny passage upstream to ocean-going Union warships, who might otherwise threaten the vital railway crossing at King’s Bridge or Savannah itself. From an initial allotment of only four smoothbore 32-pounders, McAllister’s armament had been further augmented by an 8-inch Columbiad, a 42-pounder, and a 10-inch seacoast mortar by the time that a Federal ironclad, three gunboats, and a mortar-boat came looming out of the mist at dawn of February 1, 1863, to challenge its defenses.
Capt. Robert Martin of the Georgia Light Artillery (an officer who two years previously had directed the mortar battery at Mount Pleasant, South Carolina, during the war’s opening bombardment of Fort Sumter — see above) suddenly found himself thrust into command of McAllister’s lone 10-inch mortar, and afterwards reported how he arrived at his post:
... a few minutes after 9:00 a.m. [on February 1, 1863] and immediately opened fire on the Abolition fleet. At 10:40 a.m., my platform gave way, and I was compelled to remove the planking and fire from the second tier of boards, which stood the firing very well.
Despite admitting that his “practice was at first bad,” Martin and his crew soon became very proficient. Over the next few months, accurate long-range fire from his single mortar would prove vital in driving off several more Union naval attacks.
Inevitably, though, the 60,000-man army of Maj.-Gen. William T. Sherman appeared out of the interior of Georgia from smoldering Atlanta by late autumn 1864, bound on its infamous “March to the Sea.” Bent upon linking up with the Union supply-fleet awaiting him offshore, this Federal commander closed in on Fort McAllister from its landward side by the evening of December 12, 1864. Next afternoon, its under-strength Confederate garrison of less than 200 men was overwhelmed by an assault by three Union brigades under Brig. Gen. William B. Hazen.
McAllister’s 10-inch seacoast mortar played no part in this final battle, and was photographed a few days later by Samuel A. Cooley — on December 16 or 17, 1864, according to the excellent analysis by Roger S. Durham — while it still sat forlornly mired in mud within its neglected emplacement. This weapon was disposed of shortly thereafter by Union soldiers of the 70th Ohio and 55th Illinois Infantry Regiments, but replaced in modern times by a life-size replica.
Union Mortar-Battery on Morris Island, ca. March 1865
This video-clip provides a brief camera-pan over a pair of Federal 10-inch seacoast mortars still emplaced on Morris Island, South Carolina, apparently part of the ordnance remaining in position within Battery Chatfield toward the war’s end. Given the tidy appearance of these weapons and their platforms, this scene must have been photographed during the spring of 1865, well after having last been involved in any action — the picture most likely taken by Sam Cooley or one of his assistants in late March or early April 1865. Note how a single five-man crew has been posed rather awkwardly around both mortars, distributed between this pair of weapons so as to help stage the scene.
Certain details can nevertheless be appreciated in the close-ups shown by this video-pass: for example, each mortar’s firing-vent is snugly covered with an “apron” made out of light, pliable metal, held on by a leather cinch tightened securely around the weapon’s base so as to prevent any moisture or grit from fouling this vital aperture, such as falling rain or windborne sand. Handspikes for both crews are slotted neatly against the revetment at far right, still ready to be drawn out for instant use, while an empty haversack for carrying powder-cartridges back from a service-magazine to the mortars also dangles from a peg. Note the stakes still pounded into the ground behind each mortar, as well as the advance stakes protruding from the crest of their epaulement beyond, having been driven into its sand for purposes of aiming at a distant target.
Mortars Stockpiled in a Federal Depot, April 1865
The unstoppable penetration by Sherman’s huge army into the heartland of prostrate South Carolina, meant that Charleston Harbor’s exhausted defenders at last felt compelled to withdraw on the night of February 17, 1865, from their long-held forts: Sumter, Johnson on James Island, and Moultrie on Sullivan’s Island. Next day, the besieging Union regiments would begin moving out from their positions to occupy all three of these battered strong-points — as well as the silent, ghostly City of Charleston — marking an end to all organized military resistance throughout this district. Although the Confederate government would not capitulate for another couple of months, these Federal troops were able to secure full control over the entire area around Charleston, to the extent that they even began dismantling some of their own sprawling works and encampments on Morris Island over the ensuing weeks.
This photograph from the Library of Congress, one in a series of three similar views of this depot taken by Sam Cooley or one of his assistants — most likely in April 1865, during the wait by reporters and Union dignitaries for the ceremonial restoration of Maj. Robert Anderson’s original Stars-and-Stripes flag to Fort Sumter — shows numerous artillery pieces, shells, and other bits of heavy equipment which had been unceremoniously gathered up and then dumped amid the storage sheds in this sandy compound, presumably for redistribution around the harbor-defenses, or even shipment by sea entirely out of this theater of operations. The 10-inch mortars, once one of the most powerful long-range weapons in the U.S. Artillery’s inventory prior to the war, were by now outdated relics of little appreciable military value. The 13-inch mortars had since superseded them in importance, while ordnance capable of accurately firing much heavier shells over significantly greater distances had been developed and deployed over the intervening four years of warfare.
Discarded Confederate Mortars, Fort Johnson, April 1865
Before having abandoned their strongpoint on James Island on the night of February 17-18, 1865, Fort Johnson’s Confederate garrison had first disabled all of its guns by chopping through their carriage-braces, leaving them in such a weakened state that these pieces could not safely be fired, until they had been painstakingly removed from their mountings and these wooden supports replaced. And at least three of Fort Johnson’s 10-inch seacoast mortars had likewise been temporarily incapacitated, by being left dumped on the sandy beach without their beds, so as to complicate the task for any Federal soldiers who might arrive to hoist and remount them.
The accompanying video-clip shows one of these three mortars still lying discarded on the shoreside beside what remained of Fort Johnson’s old wooden wharf. This view has been attributed to George N. Barnard and tentatively dated “March 1865,” although the flag at half-staff in the background would suggest that it might have been taken in late April 1865, during the period of public mourning after President Lincoln’s assassination. Fort Johnson’s captured Confederate ordnance remained where it had been when seized, until Company K of the 54th Massachusetts (Colored) Infantry Regiment was ordered to James Island on July 31, 1865, to assist in disassembling this antiquated weaponry and shipping it out for disposal elsewhere, a task which was completed two weeks later.
A real 10-inch seacoast mortar dating from the 1840s can still be viewed today in the Watervliet Arsenal Museum, which is located on the west bank of the Hudson River just north of Albany, New York — that particular relic having originally been cast at the West Point foundry in Cold Spring, New York. Four more mortars of this same vintage are also on display at the Civil War Memorial in Binghamton, New York, although they were actually cast somewhat later, during 1861-1862 as part of a rush-order of eighteen older-style M.1841 pieces placed by the U.S. Ordnance Department during the initial months of the Civil War. And a modern reproduction of a 10-inch seacoast mortar made by South Bend Replicas, can be examined as well at Fort McAllister, Georgia.