The sea was like molten sapphire as we glided swiftly along the southern coast of Cuba, watching the gracefully undulating shore. The mountains rose higher and higher, until they culminated in the lofty peak of Pico Turquino (blue mountain), over ten thousand feet high, as lately ascertained by actual measurement. There are coves and bays along this coast where oysters _do_ grow upon trees, ridiculous as the assertion first strikes the ear. The mangrove-trees extend their roots from the shore into the sea, to which the oysters affix themselves, growing and thriving until plucked by the fishermen. They are small and of an inferior species compared with those of our own coast, but are freely eaten in the island. Near the shore hereabouts are many islets containing from three to five square miles, some of which are quite barren, while others are delicious gardens, full of tropical fruit trees, flowers, and odoriferous plants, where Paul and Virginia might have felt quite at home, wandering hand in hand. Soon after passing the remarkably sheltered port of Guantanamo, which was for nearly a century the most notorious piratical rendezvous in the West Indies, the famous castle of Santiago is seen. It is known as Moro Castle, but it antedates the more familiar Moro of Havana by a full century. This antique, yellow, Moorish-looking stronghold--which modern gunnery would destroy in about eight minutes--is picturesque to the last degree, with its crumbling, honeycombed battlements, and queer little flanking turrets, grated windows, and shadowy towers. It is built upon the face of a lofty dun-colored rock, upon whose precipitous side the fortification is terraced. It stands just at the entrance of the narrow channel leading to the city, so that in passing in one can easily exchange oral greetings with the sentry on the outer battlement. What strikingly artistic pictures the light and shade together formed with those time-stained walls, as we steamed slowly by them! On the ocean side, directly under the castle, the sea has worn a gaping cave, so deep that it has not been explored within the memory of the people living in the neighborhood. The broad and lofty entrance is in form as perfect an arch as could be drawn by the pencil of a skillful architect. As is usual with such formations all over the world, there is a romantic legend concerning the cave related as connected with the olden time, and there is also a prevailing superstition, that no one attempting to explore it will live to return.