Some day, when you are at the seaside, take some extra water and
set it on the hob till a great deal has simmered gently away, and
the liquid is very thick. Then take a drop of this liquid, and
examine it under a microscope. As it dries up gradually, you will
see a number of crystals forming, some square - and these will be
crystals of ordinary salt; some oblong - these will be crystals
of gypsum or alabaster; and others of various shapes. Then, when
you see how much matter from the land is contained in sea-water,
you will no longer wonder that the sea is salt; on the contrary,
you will ask, Why does it not grow salter every year?
The answer to this scarcely belongs to our history of a drop of
water, but I must just suggest it to you. In the sea are numbers
of soft-bodied animals, like the jelly animals which form the
coral, which require hard material for their shells or the solid
branches on which they live, and they are greedily watching for
these atoms of lime, of flint, or magnesia, and of other
substances brought down into the sea.
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