This great Armada was very unwieldy, and contained many dull sailers, so that, making its way at the average rate of only about thirteen miles a day, it passed the Berlingas, crept by Figuera, Oporto and Vigo, and finally lay becalmed off Cape Finisterre. Up to this time the winds, if baffling, had been moderate, the weather pleasant, and the sea smooth as glass. But now the Spanish fleet was assailed by a tempest, which might be called fearful, even in the stormy Bay of Biscay. Blowing at first fitfully, and in heavy squalls, it by nightfall settled into a steady gale from west-northwest, driving before it a tremendous sea, the surges of which broke with a roar distinctly heard above the fierce howling of the wind. Yet, though the sea ran high, it was not irregular, and the Armada, under snug canvas, was making good weather of it, when, a little after midnight, the wind shifted very suddenly to northeast, blowing with the violence of a tornado, and taking every ship under square sail flat aback. Some of the vessels, gathering sternboard, lost their rudders, which were in that day very insecure; some, thrown on their beam-ends, were forced to cut away their masts and throw overboard their guns; while all lost sails and top-hamper, and not a few the upper deck cabins, at that time so lofty. When day broke the spectacle was presented of a whole fleet helplessly adrift upon the ocean. Many of the largest and finest vessels were lying in the trough of the sea, which every now and then made a clean breach over them, each time carrying off some of the crews. Among the fleet was a huge Portuguese galley, the Diana, which had been knocked down by the shift of wind, lost her masts and oars, and was lying on her side, gradually filling with water, and fast settling by the stern. The rest of the vessels were powerless to assist her, and she soon sank before their eyes, carrying down every soul belonging to her, including, of course, the poor galley slaves chained to her oars.