In the _North Pacific_ the maximum density occurs between 30° and 31° N., and the minimum in about 7½° N., in the equatorial counter current, where it was found as low as 1.02485. In the _South Pacific_, which has a slightly greater density than the North Pacific, the maximum has been found in the vicinity of the Society Islands. The density of the waters of the _Indian Ocean_ is not yet as well known as that of the Atlantic and Pacific, but the results ascertained indicate a lesser density in its northern part, with a maximum in the region between 20° and 36° S. and long. 60° to 80° E. In the vicinity of Java and Sumatra, probably on account of the extreme humidity of the atmosphere and of frequent rainfall, the density has been found as low as 1.0250. In regard to the density of the water at various depths, it has been ascertained that as a general rule it decreases from the surface down to about 1,000 fathoms, after which it increases again slowly to the bottom. In the equatorial calm regions, however, where the heavy rains dilute the surface water, the density decreases from the surface down to between 50 and 100 fathoms, after which it follows the law found for other parts of the ocean. The bottom densities of the South Atlantic and Pacific have been found about alike, varying only from 1.02570 to 1.02590; those of the North Atlantic, however, show a greater value, varying from 1.02616 to 1.02632. GREATEST DEPTHS OF THE OCEANS. ATLANTIC.--Rejecting some of the earliest soundings as untrustworthy, the greatest known depth in the North Atlantic is to the north of the island of Puerto Rico, in about latitude 19° 39' N., longitude 66° 26' W., found by the C. S. S. Blake, Lieut. Commander Brownson, U. S. N., in 1882-83, 4,561 fathoms. The deepest known spot in the South Atlantic is 3,284 fathoms, in about latitude 19° 55' S., longitude 24° 50' W., sounded by the U. S. S. Essex, Commander Schley, in 1878. The general run of the soundings indicates that greater depressions exist nearer the western than in the eastern or middle part of the Atlantic, North and South. PACIFIC.--In the North Pacific the greatest depression has been found by the U. S. S. Tuscarora, Commander Geo. E. Belknap, U. S. N., in 1874, 4,655 fathoms, in latitude 44° 55' N., longitude 152° 26' E. The next deepest sounding in the North Pacific was located by the Challenger in 1875, 4,475 fathoms, in latitude 11° 24' N., longitude 143° 16' E. As in the Atlantic, the greater depths appear to exist in the western part and particularly off the coasts of Japan. In the South Pacific the greatest depths were supposed, up to a recent period, to be in the eastern part. Within the last two years, however, the British surveying vessel Egeria has discovered greater depressions in the western part of the South Pacific, one spot sounding 4,430 fathoms in latitude 24° 37' S., longitude 175° 08' W., and another, 12 miles farther south, 4,298 fathoms.