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Clay is the precipitation of the viscid water of the sea; and is opaque, plastic, friable, capable of hardening, and fireless.
Sand is the crystallization of turbid rain-water; and is transparent, juiceless, giving sparks, durable, and capable of being vitrified.
Mould is the decomposition of fermenting vegetables; and is black, bibulous, powdery, and combustible.
Lime is the decomposition of putrescent animal substances; and is whitish, absorbent, mealy, penetrable, and effervescent.
Clay, the earth of sea-water, is hardened into talc, when redissolved is regenerated in the form of asbestus,[Pg 302] and when more intimately dissolved resumes the form of mica. Sand, the earth of rain-water, when thrown on the land and dried, forms drift-sand, which finally becomes gravel. Both substances, when under ground, are converted into sandstone, and when mixed with other matters form pebbles, which grow into stones. When redissolved and crystallized, it produces quartz. Mould, the earth of vegetables, is hardened into fissile slate, which being impregnated with bitumen becomes coal. It is dissolved into ochre, and regenerated into tophus. Lime, the wife of natron, produces marble, dissolved and saturated with acid is crystallized into gypsum. Both are decomposed by the elements into chalk, which, acted upon by rain-water, becomes flint; and when dissolved, is crystallized into spar (or calcedony).
Such are the Mothers of minerals.
It is unnecessary to follow our author, while he states the principles of his sexual system of minerals, through the forms and modifications of crystals, metals, rocks, and petrifactions. His scheme of geology may be described as follows:—The strata of the earth are generally parallel to each other, although not always so, nor always of marine origin. The lowest is of sandstone (cos), the second of slate, the third of marble filled with marine petrifactions, the fourth of slate, the uppermost of the saxose kind, which includes granite, porphyry, trap, conglomerate, and puddingstone. It is obvious that the ocean has produced the land. It is rendered turbid by nitrous showers, precipitates, and is crystallized into sand, which covers the bottom of the sea. The surface of it is here and there covered over to a great[Pg 303] extent with floating fuci, the mould derived from which gradually descends, while the lighter particles help to form a floating meadow. Marine vermes, the mollusca, testacea, lithophytes, and zoophytes, together with fishes and sea-birds, feed beneath this floating meadow. An argillaceous sediment falls down in the quiet water, and this, together with the calcareous shells of the marine vermes, gradually forms a heap, which rises to the surface, while the pressure agitating the water drives out the marine animals. On the rock thus formed, the sea casts up great quantities of fuci, which are converted into mould, until at length the sandy earth rises above the surface, dries, is driven about, and concresces into gravel and sandstone. In the course of ages, the sand is hardened into sandstone, the mould into bituminous shale and coal, the clay into marble, other layers of mould into other beds of shale or slate, and other masses of sand into gravel and conglomerate. This again is converted into pebbles, these into stones, the stones into rocks. At length, the water subsiding, the mass becomes a mountain. Had Linnæus been as unfortunate in his other theories as in this, his name would have been long ago forgotten.
However fanciful his theoretical views may be, his classification is not unworthy of praise, and his specific definitions are generally intelligible to a modern mineralogist; but this is nearly all, however, that can be said in their favour. He divides the mineral kingdom into three classes, under the names of Petræ, Mineræ, and Fossilia. These are again subdivided into several orders, and the number of genera amounts to fifty-four.[Pg 304]
Class I. Petræ or Stones, or, as modern geologists would say, Rocks.
Steril stones, originating from an earthy principle by cohesion; simple, as being destitute of salt, sulphur, or mercury; fixed, as not being intimately soluble; similar, as consisting of particles united at random.
Order I. Humosæ. Deposited from vegetable earth, combustible and burning to cinders, their powder harsh and light; as roofing-slate.
Order II. Calcariæ. Originating from animal earth; penetrable by fire, and becoming more porous, their powder mealy; and when burnt, they fall into a fine powder; as limestone, marble, gypsum.
Order III. Argillaceæ. Originating from the viscid sediment of the sea, becoming harder and stiffer in the fire, their powder unctuous before exposure to fire; as serpentine, asbestus, mica.
Order IV. Arenatæ. Originating from precipitation caused by rain-water, when struck with steel emitting sparks, very hard, their powder rough and angular like bits of glass; as quartz, jasper, flint.
Order V. Aggregatæ. Originating from a mixture of the foregoing, and therefore participating their constituent particles; their powder differing accordingly; as granite, puddingstone.
Class II. Mineræ, Minerals.
Fertile stones, originating from a saline principle by crystallization; compound, as produced from a stony substance (of the preceding class), impregnated by salt, sulphur, or mercury, intimately soluble in an appropriate menstruum, and crystalline.
Order I. Salia, Salts. To be distinguished by the taste, soluble in water; as rock-salt, alum, borax.
Order II. Sulphura, Sulphureous Minerals. Distinguishable by smell, emitting an odour and flaming under the action of fire, soluble in oil; as amber, naphtha, pyrites.[Pg 305]
Order III. Metalla, Metallic Minerals. Distinguishable by good eyes! very heavy, fusible, soluble in appropriate acid menstrua; as molybdæna, lead, gold, and copper.
Class III. Fossilia, Fossils.
Ambiguous stones, originating from modifications of the substances included in the preceding classes.
Order I. Petrificata, Petrifactions. Impressed with the form of some natural object, as,—
Zoolithus, the petrifaction of an animal of the class Mammalia.
Ornitholithus, a petrified bird.
Amphibiolithus, a petrified frog, snake, &c.
Ichthyolithus, a petrified fish.
Entomolithus, a petrified insect or crab.
Helmintholithus, of the class vermes, including shells.
Phytolithus, vegetable petrifactions.
Graptolithus, resembling figures produced by painting; as florentine and landscape marble.
Order II. Concreta, coagulated from particles agglutinated at random; as urinary and salivary calculi; tartar of wine; pumice, formed by fire; stalactite, formed by air; tophus, produced under water, as oolite.
Order III. Terræ, Earths. Pulverized, their particles loose; as ochre, sand, clay, and chalk.
