245 
der the earth, from which the waters acquire their 
acridity; and when introduced into the system, dissolve 
that with which they come in contact whether generated 
by deposition or concretion. That acids will have this 
effect, is clear, from the experiment on an egg, whose 
shell, when kept therein for some time, will be softened 
and dissolve. Lead, also, which is very flexible and 
heavy, if placed in a vessel and covered with acid, and 
there left open, will be dissolved, and become white 
lead. In the same way brass which is more solid by 
nature, if treated in the same way, will dissolve, and 
become verdigrease ; and even pearls and flint-stones, 
which neither iron nor fire can destroy, when sub- 
mitted to its action, are dissolved and dissipated by 
an acid. With these facts before our eyes, we may fair- 
ly argue, that calculous disorders may be cured by acids, 
on account of their acridity. Some springs appear to 
be mixed with wine; as that in Paphlagonia, which, 
when taken, inebriate as wine. At Æqui, in Italy, 
and in the territory of the Medulli on the Alps, there 
is a species of water, the use of which produces swell¬ 
ings of the neck. In Arcadia, at the well-known city 
of Clitorium, is a cave flowing with water, of which 
those who drink become abstemious. At the spring is 
an epigram inscribed on stone, in Greek verses, to the 
following effect: that it is not fit for bathing, and also 
that it is injurious to the vine, because, near the spot, 
Melampus cured the daughters of Prœtus of their mad¬ 
ness, and restored them to reason. The epigram is as 
follows: 
Rustic, by Clitor's stream who takest thy way, 
Should thirst oppress thee in the noon of day