from one to the other.

The most important of these with which we are acquainted is the Gulf
Stream of the Atlantic. Gathering in the South Atlantic, and passing north
through the Caribbean Sea and the Gulf of Mexico, it issues out through
the Bahama Channel, and flows north along the eastern coast of the United
States, but some distance from it, to Newfoundland, and from thence
continuing to the north-east and spreading out over the surface of the
ocean--a portion of it mingling with the waters of the North Atlantic in
passing--it flows up on the western coast of Europe, around the Faroe
Islands, and Spitzbergen, to the polar sea; passing around Greenland, and
perhaps through its Fiords, it descends again through the sounds and
channels of the Arctic regions into Baffin's Bay, and through Davis's
Straits, burdened with the icebergs and floes of the polar waters, to
return again to the South Atlantic. For reasons which will appear in the
sequel, it has comparatively little influence upon the weather of the
United States. Western Europe, however, Greenland, the islands which lie
in its course, and the polar seas, are most materially influenced.
Although not the only cause, it has very much to do with the remarkable
elevation of the isothermal lines over the Northern Atlantic, and upon
Western Europe, as seen upon the map.

A like oceanic current exists in the Pacific Ocean, the influence of which
may also be traced upon the map by the elevation of the isothermal lines
at the northern extremity of that ocean, and upon the north-west coast of
North America. A vast amount of heat is transported from the tropical to
the temperate and frozen regions of the earth by these great oceanic
currents.

Another supply is derived from aerial currents which flow from the tropics
toward the poles. These currents exist every where over the entire surface
of the earth, but in more concentrated volumes along the great "lines of
no variation," and greater magnetic intensity, on the western side of the
great oceans, over the eastern portions of the two continents of North
America and Asia. Not, as meteorological writers suppose, in the upper
portions of the atmosphere, having risen in the trade-wind region and run
off at the top toward the poles by force of gravity, but near, and
sometimes in contact with the earth. The influence of these aerial
currents upon the temperature of the atmosphere, and in producing the
phenomena we are to cons