"Every one," says Mr. Darwin, "must be struck with astonishment when he first beholds one of these vast rings of coral rock, often many leagues in diameter, here and there surmounted by a low verdant island with dazzling white shores, bathed on the outside by the foaming breakers of the ocean, and on the inside surrounding a calm expanse of water, which, from reflection, is of a bright but pale green colour. The naturalist will feel this astonishment more deeply after having examined the soft and almost gelatinous bodies of these apparently insignificant creatures; and when he knows that the solid reef increases only on the outer edge, which, day and night, is lashed by the breakers of an ocean never at rest." [Illustration: [++] Coral Reefs.] Coral being beautiful in form and colour, is sought after for purposes of ornament; and its fishery or gathering gives employment to many persons in the Red Sea, the Persian Gulf, the Mediterranean, and other places. In the Straits of Messina, the rocks which yield coral are from about 350 to 650 feet below the surface of the water. The coral here grows to about the height or length of twelve inches, and requires eight or ten years to come to perfection. In the general mode of fishing for coral, the instrument used consists of two heavy beams of wood, secured together at right angles, and loaded with stones to sink them. MILITARY HATS IN OLDEN TIME. [Illustration: No. 1, Charles I. No. 2, William III. No. 3, Nivernois. No. 4, Kevenhuller. No. 5, Ramilies. No. 6, Wellington.] WHY A MAN MEASURES MORE IN THE MORNING THAN IN THE EVENING, &c. There is an odd phenomenon attending the human body, as singular as common: that a person is shorter standing than lying; and shorter in the evening when he goes to bed, than in the morning when he rises. This remark was first made in England, and afterwards confirmed at Paris, by M. Morand, a member of the Royal Academy of Sciences in France, and by the Abbot Fontana likewise. The last-mentioned person found, from a year's experience, that ordinarily in the night he gained five or six lines, and lost nearly as much in the day. The cause of which effect, so ancient, so common, but so lately perceived, proceeds from the different state or condition of the intervertebral annular cartilages. The vertebrae, or joints of the spine, are kept separate, though joined by particular cartilages, every one of which has a spring. These yield on all sides, without any inflexion on the spine, to the weight of the head and upper extremities; but this is done by very small and imperceptible degrees, and most of all when the upper parts of the body are loaded with any exterior weight. So that a man is really taller after lying some time, than after walking, or carrying a burthen a great while.