&. PRIZE ESSAY. 
28 
SECTION y. 
OF THE ACTION OF THE SALTS OF CATTLE DUNG-. 
Here it is we find ourselves thrown on a sea of 
opinions, without chart, compass, or pilot, if we trust 
' to the conflicting theories which have been set up for 
landmarks and lighthouses. Let us, therefore, reader, 
trust to ourselves, aided by the little chemistry we 
have learned from the preceding remarks about the 
composition of salts. 
I have endeavored to impress on your memory, 
that the term salt is very comprehensive. But then 
to encourage one, it is also to be remembered, that 
salts are compounds of alkalies, earths, and metals 
with acids. Now the earths, alkalies, metals, may be 
united to each of the known acids, (and their name is 
legion,) yet you may not, by this change of acids, 
alter the nature of the earth, alkali, or metal. That 
always remains the same; every time you change the 
acid, you alter the character of the salt. Thus soda 
may be united to oil of vitriol and form Glauber’s 
salt, or to aqua-fortis and form South American salt¬ 
petre, or to muriatic acid and form common table salt. 
The soda is called the base, or basis, of this salt: that 
is always soda; you do not change its character by 
changing the acid. To give another example, lime 
may be united to carbonic acid and form chalk, or 
marble, or limestone, or it may be united to oil of 
vitriol and form plaster of Paris, or to phosphoric acid 
and form bonedust. Now, in each case, the base of 
the salt, that is, the lime, remains unchanged; but, 
changing the acid, we change the nature of the salt, 
and of course its effects will be different. 
Now it is plain, that where the base of the salt re¬ 
mains the same, that will always act the same, but 
