certain laws, constituting together a solid body; and this is termed crystallization, a form of which only certain minerals are susceptible.—Most metals, however, are supposed to take their origin from the contact or accumulation of mineral or subterraneous fumes and vapours; because the latter, which float in mines and metallic veins, at length penetrate into the particular fossil exposed to their action, and produce ore; or, they combine, each according to their peculiar species, and afford native metal.
With respect to the origin of minerals, it is probable that, in some kinds of them, a gradual refinement and change takes place within the bowels of the earth. It is also remarkable that, in the southern hemisphere, there is a greater profusion of precious metals; and these are nearer the surface of the earth, than in the northern regions.
Minerals increase in bulk only while they remain undisturbed in their natural situation; but, by exposing them to the air for a sufficient length of time, they are decomposed, or crumble to pieces, without strictly decaying, such as is the case with organized bodies.
Mineralogists divide the mineral kingdom into four classes, namely,
II. Salts.
III. Inflammable bodies; such as sulphur, bitumens, amber, rock-oil, sea-coal, &c.
IV. Metals.
Of these, however, we cannot in this place attempt an analysis; as, according to our plan, we give concise accouins of the more useful mineral bodies, in their alphabetical order.
Minium. See Red Lead, p. 76.
MINERAL WATERS, include all such fluids as are naturally impregnated with heterogeneous matter, which they have dissolved within the bowels of the earth, whether sulphureous, metallic, or saline; and, as many of these are successfully employed in medicine, they have received the appellation of medicinal waters.
Mineral waters have been divided into hot and cold, from their being either sensibly hotter or colder than the atmosphere. They have also been classed, according to their predominant ingredients, into acidulous, alkaline, martial, sulphureous, &c. It is not, however, our design to enter upon a minute investigation of their constituent parts; but, as the analysis of mineral springs may, to many inquisitive persons, afford a pleasing recreation, independently of its real utility, we shall subjoin a few rules necessary to be observed in making such experiments; together with a concise account of the waters of Acton, and Aix-la-Chapelle, referred to this article on former occasions.
I. All experiments ought to be conducted near the spring, if it be practicable.
II. The situation of such spring, the nature of the soil, and the contiguous rising grounds (if any occur) should be carefully examined.
III. With the view of analyzing the water, it will first be necessary to observe the changes it may spontaneously undergo, as well as the various parts, or matters, into which it may separate. For this purpose, it will be advisable to fill several shallow but large cylindrical glasses at the well, or spring, which should be immediately examined by the taste, eye, and smell: after which they ought to stand at
