The western Mediterranean is cut off by a bank crossing the narrow strait between Sicily and Cape Bon, usually known as the Adventure Bank, on which the depth is nowhere 200 fathoms. The mean depth of the western basin is estimated at 881 fathoms, and the deepest sounding recorded is 2040 fathoms. In the eastern Mediterranean the mean depth is nearly the same as in the western basin.
Many were taken at 10 fathoms and deeper with the line, and all were of exceptionally large size, several measuring 18 in.
The steepest slope observed occurs off the island of Sapienza, near Navarino, where 1720 fathoms has been obtained only 10 miles from land.
The greater part of the bottom of the Atlantic is covered by a deposit of Globigerina ooze, roughly the area between l000 and 3000 fathoms, or about 60% of the whole.
From the surface to 500 fathoms the general form of the isothermals remains the same, except that instead of an equatorial maximum belt there is a focus of maximum temperature off the eastern coast of the United States.
