=The Deeps of the Ocean.=--In his geographical address at the British Association, Sir John Murray showed that the deep oceanic soundings are scattered over the different ocean basins in varying proportions, that they are now most numerous in the North Atlantic and Southwest Pacific, and in these two regions the contour lines of depth may be drawn with greater confidence than in the other divisions of the great ocean basins. On the whole, it may be said that the general tendency of recent soundings is to extend the area with depths greater than one thousand fathoms, and to show that numerous volcanic cones rise from the general level of the floor of the ocean basins up to various levels beneath the sea surface. Considerably more than half of the sea floor lies at a depth exceeding two thousand fathoms, or more than two geographical miles. On the Challenger charts all areas where the depth exceeds three thousand fathoms have been called “deeps,” and distinctive names have been conferred upon them. Forty-two such depressions are now known--twenty-four in the Pacific Ocean, three in the Indian Ocean, fifteen in the Atlantic Ocean, and one in the Southern and Antarctic Oceans. The area occupied by these deeps is estimated at 7,152,000 geographical square miles, or about seven per cent of the total water surface of the globe. Within these deeps more than 250 soundings have been recorded, of which twenty-four exceed 2,000 fathoms, including three exceeding 5,000 fathoms. Depths exceeding 4,000 fathoms, or four geographical miles, have been recorded in eight of the deeps. Depths exceeding 5,000 fathoms have been hitherto recorded only within the Aldrich Deep of the South Pacific, to the east of the Kermadecs and Friendly Islands, where the greatest depth is 5,155 fathoms, or 530 feet more than five geographical miles. This is about 2,000 feet more below the level of the sea than the summit of Mount Everest, in the Himalayas, is above it. * * * * *