Amid these delays the winter expired, and scarcely had the ice begun to disappear when the construction of the bridge of boats was actively resumed by the besiegers. Between the two piers a space of more than six hundred paces still remained to be filled up, which was effected in the following manner: Thirty-two flat-bottomed vessels, each sixty-six feet long and twenty broad, were fastened together with strong cables and iron chains, but at a distance from each other of about twenty feet to allow a free passage to the stream. Each boat, moreover, was moored with two cables, both up and down the stream, but which, as the water rose with the tide, or sunk with the ebb, could be slackened or tightened. Upon the boats great masts were laid which reached from one to another, and, being covered with planks, formed a regular road, which, like that along the piers, was protected with a balustrade. This bridge of boats, of which the two piers formed a continuation, had, including the latter, a length of twenty-four thousand paces. This formidable work was so ingeniously constructed, and so richly furnished with the instruments of destruction, that it seemed almost capable, like a living creature, of defending itself at the word of command, scattering death among all who approached. Besides the two forts of St. Maria and St. Philip, which terminated the bridge on either shore, and the two wooden bastions on the bridge itself, which were filled with soldiers and mounted with guns on all sides, each of the two-and-thirty vessels was manned with thirty soldiers and four sailors, and showed the cannon's mouth to the enemy, whether he carne up from Zealand or down from Antwerp. There were in all ninety-seven cannon, which were distributed beneath and above the bridge, and more than fifteen hundred men who were posted, partly in the forts, partly in the vessels, and, in case of necessity, could maintain a terrible fire of small-arms upon the enemy.
But with all this the prince did not consider his work sufficiently secure. It was to be expected that the enemy would leave nothing unattempted to burst by the force of his machines the middle and weakest part. To guard against this, he erected in a line with the bridge of boats, but at some distance from it, another distinct defence, intended to break the force of any attack that might be directed against the bridge itself. This work consisted of thirty-three vessels of considerable magnitude, which were moored in a row athwart the stream and fastened in threes by masts, so that they formed eleven different groups. Each of these, like a file of pikemen, presented fourteen long wooden poles with iron heads to the approaching enemy. These vessels were loaded merely with ballast, and were anchored each by a double but slack cable, so as to be able to give to the rise and fall of the tide. As they were in constant motion they got from the soldiers the name of "swimmers." The whole bridge of boats and also a part of the piers were covered by these swimmers, which were stationed above as well as below the bridge. To all these defensive preparations was added a fleet of forty men-of-war, which were stationed on both coasts and served as a protection to the whole.
This astonishing work was finished in March, 1585, the seventh month of the siege, and the day on which it was completed was kept as a jubilee by the troops. The great event was announced to the besieged by a grand /fete de joie/, and the army, as if to enjoy ocular demonstration of its triumph, extended itself along the whole platform to gaze upon the proud stream, peacefully and obediently flowing under the yoke which had been imposed upon it. All the toil they had undergone was forgotton in the delightful spectacle, and every man who had had a hand in it, however insignificant he might be, assumed to himself a portion of the honor which the successful execution of so gigantic an enterprise conferred on its illustrious projector. On the other hand, nothing could equal the consternation which seized the citizens of Antwerp when intelligence was brought them that the Scheldt was now actually closed, and all access from Zealand cut off. To increase their dismay they learned the fall of Brussels also, which had at last been compelled by famine to capitulate. An attempt made by the Count of Hohenlohe about the same time on Herzogenbusch, with a view to recapture the town, or at least form a diversion, was equally unsuccessful; and thus the unfortunate city lost all hope of assistance, both by sea and land.
These evil tidings were brought them by some fugitives who had succeeded in passing the Spanish videttes, and had made their way into the town; and a spy, whom the burgomaster had sent out to reconnoitre the enemy's works, increased the general alarm by his report. He had been seized and carried before the Prince of Parma, who commanded him to be conducted over all the works, and all the defences of the bridge to be pointed out to him. After this had been done he was again brought before the general, who dismissed him with these words: "Go," said he, "and report what you have seen to those who sent you. And tell them, too, that it is my firm resolve to bury myself under the ruins of this bridge or by means of it to pass into your town."
But the certainty of danger now at last awakened the zeal of the confederates, and it was no fault of theirs if the former half of the prince's vow was not fulfilled. The latter had long viewed with apprehension the preparations which were making in Zealand for the relief of the town. He saw clearly that it was from this quarter that he had to fear the most dangerous blow, and that with all his works he could not make head against the combined fleets of Zealand and Antwerp if they were to fall upon him at the same time and at the proper moment. For a while the delays of the admiral of Zealand, which he had labored by all the means in his power to prolong, had been his security, but now the urgent necessity accelerated the expedition, and without waiting for the admiral the states at Middleburg despatched the Count Justin of Nassau, with as many ships as they could muster, to the assistance of the besieged. This fleet took up a position before Liefkenshoek, which was in possession of the Spaniards, and, supported by a few vessels from the opposite fort of Lillo, cannonaded it with such success that the walls were in a short time demolished, and the place carried by storm. The Walloons who formed the garrison did not display the firmness which might have been expected from soldiers of the Duke of Parma; they shamefully surrendered the fort to the enemy, who in a short time were in possession of the whole island of Doel, with all the redoubts situated upon it. The loss of these places, which were, however, soon retaken, incensed the Duke of Parma so much that he tried the officers by court-martial, and caused the most culpable among them to be beheaded. Meanwhile this important conquest opened to the Zealanders a free passage as far as the bridge, and after concerting with the people of Antwerp the time was fixed for a combined attack on this work. It was arranged that, while the bridge of boats was blown up by machines already prepared in Antwerp, the Zealand fleet, with a sufficient supply of provisions, should be in the vicinity, ready to sail to the town through the opening.
While the Duke of Parma was engaged in constructing his bridge an engineer within the walls was already preparing the materials for its destruction. Frederick Gianibelli was the name of the man whom fate had destined to be the Archimedes of Antwerp, and to exhaust in its defence the same ingenuity with the same want of success. He was born in Mantua, and had formerly visited Madrid for the purpose, it was said, of offering his services to King Philip in the Belgian war. But wearied with waiting the offended engineer left the court with the intention of making the King of Spain sensibly feel the value of talents which he had so little known how to appreciate. He next sought the service of Queen Elizabeth of England, the declared enemy of Spain, who, after witnessing a few specimens of his skill, sent him to Antwerp. He took up his residence in that town, and in the present extremity devoted to its defence his knowledge, his energy, and his zeal.