ing by its extreme volatility. Every metal deprived of this
igneous principle is immediately reduced to a calx, and thus deprived
of its splendour, fusibility, and other properties, until restored
again by the readmission of its phlogiston. Calcined lead having lost
this inflammable quality, is reduced to a red calx or mineral earth,
which, if fluxed with any igneous body, such as oil, pitch, wax, fat,
wood, bone, or mineral oil or bitumen, the fiery principle is resorbed,
and the lead restored to its essential qualities; from these physical
observations the reader may be convinced of those mineral waters as
afford such a sediment being in a state of decomposition. They are thus
deprived of one of the four elements or principles of which they are
all more or less composed. Every analysis of mineral waters in their
perfect state has demonstrated that they possess a fixed air, a
volatile alkali, a volatile vitriolic acid, and the phlogiston. If,
therefore, either of these essential qualities is evaporated or
corrupted, the water, being in a state of decomposition, must lose the
virtues of a medicinal chalybeate.

It is only necessary to add a few further remarks, in order to shew in
what particular complaints chalybeates, even in their most perfect
state, are pernicious. By this means many of the diseased will be
guarded against a fatal error: and as the prejudice in favour of such
applications is so universally prevalent, it is hoped a few pages
allotted to this subject will be deemed a most essential service to a
deluded community. By removing such a pernicious partiality, the
health, if not the lives of thousands, may be saved, to the great
enjoyment of themselves and their relatives. Dr. Knight says very
justly, "that the explication of the manner of the operation of
chalybeate medicines in human bodies is grounded upon false principles,
and not matters of fact; to wit, that all chalybeate preparations, in a
liquid form, owe their medicinal efficacy to the metal dissolved,
whether in an aqueous or spirituous menstruum, retaining its metallic
texture." To avoid entering into the whole detail of this interesting
argument, it is only here stated in support of the above assertion,
that as mineral waters are impregnated with a combination of sulphurs,
salts, and earth, their virtues cannot be properly ascribed, as they
have been, to the metals which they contain. It might be further
proved, that iron cannot possibly enter