The forts of Saint Philip and St. Mary, at either end of the bridge, had each ten great guns, and both were filled with soldiers. In front of each fort, moreover, was stationed a fleet of twenty armed vessels, carrying heavy pieces of artillery; ten anchored at the angle towards Antwerp, and as many looking down the river. One hundred and seventy great guns, including the armaments of the boats under the bridge of the armada and the forts, protected the whole structure, pointing up and down the stream. But, besides these batteries, an additional precaution had been taken. On each side, above and below the bridge, at a moderate distance--a bow shot--was anchored a heavy, raft floating upon empty barrels. Each raft was composed of heavy timbers, bound together in bunches of three, the spaces between being connected by ships' masts and lighter spar-work, and with a tooth-like projection along the whole outer edge, formed of strong rafters, pointed and armed with sharp prongs and hooks of iron. Thus a serried phalanx, as it were, of spears stood ever on guard to protect the precious inner structure. Vessels coming from Zeeland or Antwerp, and the floating ice-masses, which were almost as formidable, were obliged to make their first attack upon these dangerous outer defences. Each raft; floating in the middle of the stream, extended twelve hundred, and fifty-two feet across, thus protecting the whole of the bridge of boats and a portion of that resting upon piles. Such was the famous bridge of Parma. The magnificent undertaking has been advantageously compared with the celebrated Rhine-bridge of Julius Caesar. When it is remembered; however; that the Roman work was performed in summer, across a river only half as broad as the Scheldt, free from the disturbing, action of the tides; and flowing through an unresisting country; while the whole character of the structure; intended only to, serve for the single passage of an army, was far inferior to the massive solidity of Parma's bridge; it seems not unreasonable to assign the superiority to the general who had surmounted all the obstacles of a northern winter, vehement ebb and flow from the sea, and enterprising and desperate enemies at every point.