16 
AMERICAN GEOLOGY. 
stony matters upon the earth’s surface. Chemical action has 
separated these elements, and united them again so as to form 
this compound. It is dissolved by the streams, and transported 
to the ocean, which has become salt by small additions from 
time to time. The water of the ocean which is carried off by 
evaporation is fresh; and hence, while water continually flows 
in charged with a little salt imperceptible to the taste, and none 
is carried off, it will finally become salt. In shallow seas or 
bays in warm climates, where evaporation is rapid, salt is 
rapidly formed; and though it may be mixed with mud, yet 
when it crystalizes, as it always will, it becomes pure. Layers 
of crystals are successively formed under favorable conditions, 
and these united form thick beds of salt. The quantity of salt 
in the oceans and seas is enormous, and long periods must have 
passed before it became perceptible to the taste. The small 
quantity of salt in the water in the early periods may have 
modified the forms both of animals and vegetables. Brine 
springs may originate from beds of rock salt, or water in the 
deep parts of the earth’s crust, and by the aid of chemical 
affinity may form common salt from its elements. These ele¬ 
ments are known to exist there; and the water being charged 
with salt, rises to the surface as brine springs, or else the brine 
may remain below in reservoirs until they are reached by the 
industry of man. The brines or salines of New York seem to 
be formed in this way; that is, from the elements of salt which 
exist in the rocks in other combinations. 
Water, then, acting as a solvent, produces many important 
changes upon the earth’s surface. It dissolves and consolidates 
rocks when aided by carbonic acid, heat, and pressure. It dis¬ 
solves and transports the saline bodies to the common reservoirs, 
where they are concentrated by one of the natural processes— 
that of solar evaporation. It is a result of the utmost import¬ 
ance to the well being of man. 
Bodies of salt water are never formed so long as there is a 
supply of rain to maintain a drainage to the ocean. If, how¬ 
ever, the rains only supply sufficient water to fill a basin, and 
