DEFENDING SAN MARCOS

The Castillo de San Marcos was a typical example of European design transplanted to the Western Hemisphere. It was a style of fortification evolved from the medieval castle. There was no great change in siegecraft and fortification until the gunpowder cannon came into use, but when that weapon did make its appearance the military engineers found themselves in a predicament. The towering walls of the ancient castles were conspicuous targets for the skilled artillerist. Adamant stone walls that had splintered the powerful crossbow shaft and resisted for days on end the pounding of the catapults tumbled into rubble after a roaring bombardment from heavy siege cannons. So the engineers lowered their targetlike walls, and in front of them they piled thick and high hills of earth to stop the cannonballs before they could hit the stone. Yet, because those walls still had to be too high for the scaling ladders, the surrounding moat was retained. Circular towers common to the older castles eventually gave way to the more scientific bastion, an angular salient from which the pikemen, harquebusiers, and artillerists could see to defend every adjacent part of the fort walls. The ultimate result was a rather complicated series of straight walls and angles—a sort of defense-in-depth plan—and in the center of it could usually be found the garrison quarters and the magazines.

Fortification was a remarkably exact science, and one that was universally respected. "Many ... arguments, wrote an eighteenth-century expert, "might be alledged to prove the usefulness of fortified places, were it not that all the world is convinced of it at present, and therefore it would be needless to say any more about it." A fort, however, can never win a victory. Primarily a defensive weapon, it protects vital points and delays the invader. It can also be, as was the case with the historic fort in Florida, a citadel and a pivot of maneuver for colonial troops.

For most defense problems, there was an answer in the book, though the brilliance of the engineer might well be measured by his ingenious use of natural defenses, as was the case at Castillo de San Marcos. There were as many different kinds of forts as there were uses for them. They promoted and protected trade, they guarded the pass into a country, or, like San Marcos, they secured the country from invasion. The following dogma, written three-quarters of a century after the castillo was started, might have referred specifically to the fort at St. Augustine: "In small states . . . which cannot afford the expense of building many fortresses, and are not able to provide them when built with sufficient garrisons and other necessaries for their defence, or those whose chief dependance consists in the protection of their allies; the best way is to fortify their capital, which being made spacious, may serve as a retreat to the inhabitants in time of danger, with their wealth and cattle, till the succours of their allies arrive.

To attack a seventeenth- or eighteenth-century fort, the enemy had first to cross natural barriers, advance over level ground where he was exposed to fire from almost every part of the fortification, drive the defenders from the outer works, cross the moat, and then, if there were any of him left, scale the main walls and fight the rest of the defenders hand to hand. It was no easy job. His approach to within striking distance generally involved the laborious digging of zigzag trenches up to the outworks. Meanwhile, his artillerymen tried to get their guns close enough to breach the walls.

Aside from the actual fighting, a serious problem was supplying provisions for the large besieging force, since the invading army was often far from its base and to some extent had to live off hostile country. On the other hand once the attacker brought his artillery to bear, the garrison and refugees found themselves in the unpleasant position of stationary targets, subjected to devastating fire, particularly from the heavy mortars throwing 50- or 100-pound bombs (exploding shells) into the close confines of the fortification. And if the enemy isolated the fort, as he invariably tried to do, the length of the siege was often proportionate to the amounts of food and water inside the fort. For this reason, at least 5 of the 20 main rooms in Castillo de San Marcos were given over to food storage, and three wells were dug in the courtyard. As long as the provision magazines were well filled, the citadel was strong.

The test of its strength was not long delayed, for the border squabbles between Spaniard and Englishman soon flamed into open warfare. The Florida Governor, Joseph de Zuniga, a Flanders veteran well-versed in the art of fortification, looked at the St. Augustine defenses with jaundiced eye. True, the castillo was a bulwark, but its guns were not only obsolete—many of them were unserviceable. The heavy powder supplied from New Spain so fouled the gun barrels that after "four Shots, the Ball would not go in the Cannon." Harquebuses, muskets, powder, and shot were sorely needed. Captain Ayala, again sailing to Spain for aid, was racing against time; it was 1702 and James Moore, Governor of Carolina, was already marching on St. Augustine.

At this critical hour, help came from Havana. Threescore skilled Gallegos (Spanish soldiers native to Galicia) arrived in Florida and set about reconditioning the ordnance, but before Spanish preparations were completed Moore's forces arrived, encircled the fort, and occupied the houses of the townspeople, who could do nothing other than flee to the shelter of San Marcos. On the south side of the fort where the outskirts of the town crept near, the Spanish burned many of their houses which might have given shelter to English troops advancing toward the fort.

Moore's fighting forces of 800 Englishmen and Indians vastly outnumbered the Spanish garrison, but he was ill-equipped to besiege the fortification. Four cannons he had, and the Spanish boasted that a continuous fire from the fort walls kept him out of range. Indeed the Gallegos were useful! Moore settled down to await the arrival of more artillery from Jamaica, and thus matters stood when a pair of Spanish men-of-war sailed from the south and blocked the harbor entrance. With little hesitation, Moore burned his eight vessels, left many of his stores, and retreated over land to his province, leaving much of St. Augustine in ashes.

The Spanish estimated that the damage to the town amounted to 20,000 pesos or more, and the ease with which the English had occupied and held the town for almost 2 months made it clear that additional fortifications had to be built. In the quarter century that followed, out from the castillo went strong earthworks and palisades, strengthened at strategic points with redoubts, and St. Augustine became a walled town, secure against invasion as long as there were enough soldiers to man the walls. The years of building these town defenses were lean years. In 1712 came la Gran Hambre—the Great Hunger—and in those dark days the starving people ate even the dogs and cats until the storms isolating the colony finally abated.

But the work was done, and when in 1728 another South Carolinian, Colonel Palmer, marched against the presidio, the sight of the grim walls of the fort, the unwinking readiness of the heavy guns, and the needle-sharp points of the yucca plants lining the town palisades were a powerful deterrent. He "refrained" from taking the town. For their part, the Spaniards set off their artillery, but they made no sorties.

Nevertheless, Palmer's bold march to the very gates of St. Augustine foreshadowed coming events, and the Spaniards again made ready, for the castillo now began to show its half-century age and the wooden palisades were rotting. That capable engineer and frontier diplomat, Don Antonio de Arredondo, came from Havana to inspect the Florida fortifications and make recommendations. Backed by Arredondo's expert opinions, Governor Manuel de Montiano put all the cards on the table in a letter to the Havana Governor: "For Your Excellency must know that this castle, the only defense here, has no bombproofs for the protection of the garrison, that the counterscarp is too low, that there is no covered way, that the curtains are without demilunes, that there are no other exterior works to give them time for a long defense; but that we are as bare outside [the castle] as we are without life inside, for there are no guns that could last 24 hours, and if there were, we have no artillerymen to serve them."

Unlike many of his predecessors, Montiano had the ear of the Cuban Governor. Guns and men came from Havana. There was money to strengthen the fortifications and in the summer of 1738 began the work of tearing down the old rooms inside the fort and laying foundations for the 28 great arches that were to make the new rooms proof against English bombs. While the carpenters were setting up the forms for the arches, while the quarries and the limekilns were again the scenes of feverish activity, James Oglethorpe in his buffer colony of Georgia was growing stronger and stronger, pushing the Florida boundary ever closer to the St. Johns River—a scant 35 miles north of the castillo.

Then the ponderous arches were finished and hurriedly leveled off with a packed fill of coquina chippings, sand, and shell. Hundreds of bushels of lime went into the tabby or mortar that was spread over the entire roof of the renovated fort to make its terreplein. The tampers beat the wet mixture smooth, and when the first layer was hardened, another and another was added until there was a bed of tabby 6 inches deep. Upon this smooth, hard surface the cannoneers could maneuver their heavy guns and the rooms below were safe under 2-1/2 feet or more of solid masonry; in fact, on the eastern side, where heavy bombardment was most likely, the engineer allowed a minimum thickness of 4 feet. Some of the parapets had to be rebuilt for modernization. Outside the fort a new stockade was erected to strengthen the covered way, and the walls enclosing the town were reworked. Under Montiano's dynamic leadership and the able supervision of Engineer Pedro Ruíz de Olano, the work was practically finished by 1740. There was no time to spare.

The War of Jenkins' Ear precipitated Oglethorpe's invasion of Florida. When the first English warship appeared off the bar of St. Augustine in June (by the Spanish calendar) of 1740, Montiano hastily sent the news to Havana: here was the long-expected Siege of St. Augustine. Reenforcements had brought the 350-man garrison up to about 750 against General Oglethorpe's force of about 900 soldiers, sailors, and Indians. Oglethorpe landed his guns across the bay from the fort, and as British shells began to burst over the town, the inhabitants, almost 2,000 of them, fled to the fort. "It is impossible," wrote Montiano to the Governor of Cuba, "to express the confusion of this place . . . though nothing gives me anxiety but the want of provisions, and if Your Excellency . . . cannot send relief, we must all indubitably perish." There was no hint of surrender.

For 27 nerve-shattering days the English batteries thundered at the castillo. Newly laid stones at the eastern parapet scattered under the hits, but the weathered old walls of the curtains held strong. As one Englishman observed, the native rock "will not splinter but will give way to cannon ball as though you would stick a knife into cheese..." One of the balls shot away an artilleryman's leg, but only two of the persons sheltered in the fort were killed in the bombardment. The heavy guns of San Marcos and the long-range 9-pounders of the maneuverable Spanish galleys in the harbor held the enemy at bay.

A league to the northward was Fort Mosa, abandoned outpost at the village of run-away Negroes. Oglethorpe's Highlanders occupied it. At dawn, June 26, 1740, a sortie from the castillo surprised the Scotchmen and in the bloodiest action of the entire siege the Spaniards drove out the enemy and burned the palisaded fortification. After that blow, the siege dragged along. While General Oglethorpe and his men battled insects and shifting white sand on the barren, sun-parched shores across the bay, the Spaniards in the cramped quarters of San Marcos watched their supplies dwindle dangerously low. Before long, Montiano's effective troops were reduced by more than half. Nor were the refugees in better shape. Just when the future looked darkest, news came that provisions from Havana had reached a harbor south of Matanzas, far down the coast. Skillfully avoiding the English blockade, Spanish seamen began to bring the provisions along the inland waterway. Oglethorpe made ready to assault the fort, then thought better of it, for the storm season was approaching, his ships were in danger, and his men were disheartened. To the wonderment of Montiano, the Georgia general suddenly raised the siege on its 38th day and marched back to the north.

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