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 from that depth downward, the thermometer shows a uniform temperature of from 33° to 34° F., and the copper cases enclosing the thermometers come up from the bottom feeling very cold.

In September 1873, the Tuscarora sounded 1100 miles on a great circle from Cape Flattery, Washington Territory, towards Atcha, one of the Aleutian Islands. The work was then suspended owing to the lateness of the season. About 200 miles from Cape Flattery, a submarine elevation of 1800 feet was found, which is probably an under spur from Vancouver Island. From that point to the locality where the ship stopped work, the bottom descends in a remarkably regular manner, averaging a fall of about six feet per mile. Indeed, that part of the Pacific bed may he likened to a section of an immense shallow bowl, so gentle and regular is the curve of descent.

The character of the bottom varied considerably, mud, stiff clay, ooze, sand, pebbles and shingle being brought up at different points on the line sounded; in that respect differing materially from the character of the soil on the telegraphic plateau of the North Atlantic, which is almost precisely uniform in its nature throughout its whole extent.

On the way back to San Francisco, and from San Francisco to San Diego, soundings were made off and on the coast to determine the “True continental outline, or the beginning of the ocean bed proper.” The result shown was, that a slope or terrace, from 10 miles to 50 miles in width, makes off from the coast line in comparatively shoal water, and then drops very abruptly down to depths of 1,500 fathoms and 2,000 fathoms, constituting an immense buttress, as it were, to support the continent.

While sounding late one afternoon, some 140 miles off the coast of California, the lead suddenly brought up at a depth of 996 fathoms, where a depth of 1,600 fathoms or 1,700 fathoms was looked for. No specimen came up and the point of the end was found to be battered.

Sounding round the locality it was found that a rocky