On most ships the clock in the companion way is set back or forward at midnight, and there is not another change for twenty-four hours.
Saturday, February 15.—People living in a dry
country a long way from the sea do not realize that
it covers three-quarters of the surface of the earth.
Ninety-six per cent of the water in the ocean is pure
fresh water, yet so great is the bulk of sea-water that
the total amount of salt dissolved in it, if deposited in
a layer over the surface of the land, would make a bed
over four hundred feet thick. . . . No one is able
to say what is the source of the salt in the ocean.
Probably the sea has always been salt, having become
so when first the waters gathered on the surface of the
globe; but all rivers that flow over the land carry salt,
which they have obtained from the rocks and soil, so
the sea is probably becoming saltier all the time, just
as some lakes without outlet are being transformed to
salt seas. . . . Off the coast of Australia for fifty
or a hundred miles, the sea is two hundred to four hundred
feet deep, but the depth grows greater as you leave
the land, and between Australia and Africa, in places,
the depth is more than five and a half miles, being
greater than the elevation of the highest land above the
sea-level. It has been calculated that the average
depth of the ocean is more than 12,000 feet. The
plains of the ocean bottom are the most extensive in
the world. Here and there these plains are relieved
by single peaks, like Bermuda, or groups of peaks, like
