20 THE OCEAN. 
the sea than in a river. Now, superior buoyancy 
seems an important advantage in a fluid which bears 
on its bosom the commerce of the world. It is 
highly probable, then, that our gracious God .had 
the convenience and benefit of man in view when 
he ordained the sea to be salt. The Ocean contains 
three parts in every hundred of saline matter, chiefly 
muriate of soda, or the common salt of the table, 
which is a chemical compound of muriatic acid and 
soda. The proportion is rather large in the vicinity 
of the equator. If we considered only the immense 
amount of evaporation which is daily going on from 
the sea, we might suppose that, like a vessel of the 
fluid exposed to the sun, it would diminish in 
volume and increase in saltness, until at length 
nothing would be left but a dry crust of salt upon 
the bottom; on the other hand, looking alone at 
the many millions of tons of fresh water which 
are every moment poured into its bosom from the 
rivers of the earth, we might apprehend a speedy 
overflow, and a second destruction by a flood. But 
these two are exactly balanced; the water taken up 
by evaporation is with scrupulous exactness restored 
again, either directly, in rain which falls into the sea, 
or circuitously, in the rain and snow, which falling 
on the land, feed the mountains, streams and rivers, 
and hurry back to their source. This interesting 
circulation had been long ago observed by the wisest 
of men: “All the rivers run into the sea; yet the 
sea is not full; unto the place from whence the 
rivers come, thither they return again.”* And a 
* Eecles. i. 7. 
