Page:Polar Exploration - Bruce - 1911.djvu/188

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184
POLAR EXPLORATION

an undoubted aid towards the solution of the meaning of this very cold water at the bottom of the ocean off the east coast of South America northward toward the equator. The lowest bottom temperatures obtained by the Scotia were 28.9° F. in 2,550 fathoms in 63° 51′ S., 41° 50′ W.; 30.95° F. in 2,547 fathoms in 64° 24′ S., 48° 18′ W.; 31.0° F. in 1,775 fathoms in 62° 10′ S., 41° 20° W.

The bottom temperatures taken by the Scotia farther south are considerably higher, and in the vicinity of where Ross thought he had "4,000 fathoms no bottom," namely, in 68° 32′ S., 12° 49′ W., the Scotia obtained a bottom temperature in 2,485 fathoms of 31.5° F.

It is very tempting to suppose that, like the Gulf Stream in the north, there is a warm highly saline current pushing southward along the surface from the Atlantic, which dips under the colder but less saline water on the surface of the Antarctic seas, and that getting cooled, this water sinks whilst abutting against the Antarctic continent, and by the ever-flowing southward upper current is pushed northward underneath along the floor of the ocean, finding its way into the deeps to the east of South America. The Scotia salinity observations also seem to support this theory, especially the record in 159 fathoms two miles off Coats Land, But this hypothesis is here given with all cau-