Many portions of the land and sea extend reciprocally the one into the other. If the sea penetrate into the interior of any continent, it forms there a _mediterranean_, or inland sea, almost surrounded by land, and having only a narrow opening into the sea. If the extent of such seas be less, and the opening larger, they are called _gulfs_ or _bays_, two terms which geographical writers have wished to distinguish, but which customary language more frequently confounds. The still smaller portions of sea, surrounded as it were by land, and which afford a shelter for ships, are called ports, creeks, or roads. The first term means a secure asylum; the second is applied to places or ports of much smaller size, and which, when improved or completed by artificial aid, are styled harbors, and roads afford only a temporary anchorage and security from certain winds. The principal bays in the world are Baffin’s, Hudson’s, James’s, Fundy, Massachusetts, Narraganset, Delaware, Chesapeak, Campeachy, Honduras, Bristol, All Saints, Cardigan, Donegal, Galway, Biscay, Bengal, Walwich, Table, False, Angola, Natal, Saldanha, and Botany. The principal gulfs are St. Lawrence, Mexico, Amatique, California, Panama, Guayaquil, St. George, Bothnia, Finland, Riga, Genoa, Naples, Taranto, Venice, Salonica, Persian, Ormus, Siam, Tonquin, Corea, Obi, and Guinea. The principal sounds are Long Island, Albemarle, Pamlico, Prince William’s, Queen Charlotte’s and Nootka. CHAPTER XII.――OCEANS. THE United States are washed by the _Atlantic Ocean_ on nearly the whole of their eastern coast, and by the _Pacific_ on a large portion of their western boundary. Under the name of the _Atlantic_, is comprised that mass of water between the eastern coast of America and the western coast of Europe and Africa. In its narrowest part, between Europe and Greenland, it is one thousand miles wide, and opening thence to the south-west with the general range of the bounding continents, spreads under the northern tropic to a breadth of sixty degrees of longitude, or four thousand one hundred and seventy miles, without estimating the Gulf of Mexico. The general phenomena on the two opposing sides of the Atlantic have great resemblance. The Atlantic coast of the United States presents an elliptic curve in its entire extent, with three intermediate and similar curves; the first extending seven hundred miles from Cape Florida to Cape Hatteras, the second from Cape Hatteras five hundred miles to the outer capes of Massachusetts, and the third formed by the coasts of Massachusetts, New Hampshire and Maine. Opposite to the United States, the Atlantic admits soundings in every place near the shores, always deepening very gradually. We have not found an exact comparison of the natural history of the Atlantic with that of other oceans. The chief phenomenon that marks it along the coast of the states is the Gulf Stream.