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bafter, Loadstone, Marble, Flint, Pebble ; and -4°. Earths, which are either fatty, as the Boles, Clay, Fullers Earth, &c.or Dryer, as Chalk
and Oker. Semi
Semi-Metals are such Bodies as “ either conmetals “ tain the known and true Metals, or Bodies what.
6c so like thereto, as that they may almost pass 2:53: 66 for the same."
The Species hereof are either, 1o. such as confift of a true Metal, and a Salt; such as are Vie triols, both Green, Blue, White, Cyprian, &c. or, 29. of Sulphur and a Metal, to which belong native Cinnabar, Antimony, Bismuth and Zink. 39. Among Semi-Metals are also rankedall cryfa talline, ftony, and earthy Matters, which are Metals intermixed with them ; such are most na
tive Ores, the Lapis Lazuli, Armenus, Hæma. tites, Loadstone, &C. Principles This History of Fosfils, is closed with an account of Fossils. of their Principles, which the Author reduces to
Mercury, metallic Sulphurs, Salts, combustible
Acid. Vegetables From Fossils, the Author proceeds to Vegewhat. 57• tables, which he defines to “be humid Bodies,
« containing different Juices, in various Vessels, " and adhering by some external Part to another « Body, from whence they derive the matger of « their Growth and Nutriment."
Hence he descends to a detail of the several Parts of Plants; as the Root, Leaves, Flowers, and Bark; gives their Structure and Office, the Juices contained in them, as Honey, Balm, Oil, Colophony, Gum and Rofin. -Beside these, which are common to all Plants, each has a peculiar Juice, which is formed by the joint force and result of all the parts of the Body, successively applied to the cruder Juice ; and being thus prepared, contains the true
characteristic Properties of that Plant, and the Virtues arising from them.
The Chapter is closed with an account of the Principles Principles of Plants, which he shews to be the Of Lege
tables. Spiritus rector, or presiding Spirit ; a fovereign *** Oil, the Seat of this Spirit, an acid Sali, a neutral Salt, an alcaline Salt, a faponaceous Juice, an Oil strongly adhering to the Earth ; and lastly, Earth itself, the Basis of all the rest.
Animals he defines to be “ humid Bodies, 62. " which live by a continu::), determinate Mo- Animals. • tion of Juices in their Vessels ; and contain-what. « ing vascular Parts, whereby, as with Roots, " they imbibe the matter of their Growth and 66 Nutriment.” · The Vessels which do this office of Roots, are found in most kinds of Animals, feated in the cavity of their small Guts, and known by the Names of Lasteals and Mesenterics: the Meat and Drink brought to the absorbent Mouchs of these Vessels afford the nutrimental Part, and supply the office which the Earth does to Plants.
The similitude and diversity between Vegetables and Animals, is further illustrated by the
Author, both as to their Structure, Manner of Generation, Nutrition, 30,- In these, as in the other, the Food continually recedes the further from its former nature, and approaches nearer to the Properties of the Animal, the longer it is circulated thro' the parts of the Body.
The Principles of Animals are, first, a fine sub. Principles til Spirit continually exhaling from them, wherein of Animals. their proper Character seems to be lodged, whereby they are diftinguished from all others.
29. Water, which affords the chief matter of most other Bodies, does the same in respect of the Humours of Animals; which also, 3o. contain
A a 4
a peculiar Salt never found fixed, nor yet so 'volatile, as to exhale by the greatest Heat a healthy Animal is capable of: neither is it acid, nor yet alcaline as it exists in the Animal, tho' by Putrifaction and Fire, it may be rendered wholly alCaline. Of itself it approaches nearest the nature of Sal Armoniac; from which, however, it differs in certain Circumstances. The Author after a Multitude of Experiments, to determine the nature of this Salt, finds it to be mild and saponaceous ; and concludes it formed of a concrete · Oil, of a middle nature between the other Salts. '4". Oils, which are found of different kinds in the Body, some miscible with Water, and eafily volatile ; others extremely mild, and scarce saline, &C.-Lastly, the Basis of the Body is Earth, which appears, the same in Animals as
in Vegetables.p. 70.
10. Having dispatched the Object of Chemistry, Operations the Author proceeds to the Astions or Operations of Che
thereof. The business of Chemistry is to change mistry.
the several Bodies of the three Classes above specified; which Change, he shews, is produced in them by means of Motion. Now Motion may either be excited a-new, or suppressed when already raised or changed in its degree, by increasing or diminishing it ; or the Quantity of it may remain the faine, and only its Course and Direction be changed : and all these again may either be in respect of the whole Mass, or of some part thereof. From which few simple conditions, all the different Effects of Chemistry, how numerous soever, do arise. The Chemists, it is true, would have us think there is more myftery in the matter ; but this is only matter of craft. All their Calcinations, Fixations, Vitrifications, Sublimations, Fermentations,, Putriface.
tions, Digestions, and other Operations are in ef. feet reducible herero.'
Nor does it appear, that the Art gives the true Principles Principles of things ; or that we may judge of chemic. if
genuine. the Compounds by the Simples into which they de are chemically reducible: since the Separation of Parts, thus effected, does not shew that those Parts had pre-existed in the Body: the Operations whereby they become separated from the rest, may make great Alterations in them, and even give them new Powers. In Nature, there appear to be Corpuscles unchangeable by any Cause hitherto observed, on account of their extream hardness. So that when the Analysis of a Body has reduced it into these, there is an . end of all Division: these Parts are called Elements ; and into these the Chemists have often in alledged, that Bodies are resolved by their Operations : but it may be doubted whether such Bodies can by any Contrivance be procured-and exhibited perfectly pure. - The Author sug: gests many things to shew they cannot : in effect, the Limits of the Power of Chemistry, as alligned by Dr. Boerhaave, are, that from any determinate kind of Bodies, a certain determinate Operation will always produce certain determinate effects: but whether the matters'thus produced actually exifted in the Body, before the Operation, is not easy to say.. .
From the Action he proceeds to the Effe Ets p. 79. produced by Chemistry, the principal whereof Effects of are reduced to four Classes or Kinds, viz. Extrakts, Clyfus's, Magisterys and Elixirs ; the specific Characters of each whereof he lays down, indicating the several other more particular Ef- ... fects and Operations reducible to each of them.. Not that the terms above mentioned are used
uniformly among all Authors: some take more Properties into their Ideas of them, other fewer ; the Author leaves every body to their choice, and only says he has good Vouchers for that choice he has made.
Hence he proceeds to the uses of Chemistry; Uses of which he illustrates in several Sciences and Arts, in pbysics. om beginning with Natural Philofopby; where Fire,
which is the great Instrument of Chemistry, is also the usual means which Nature makes use of
in producing most Physical Phænomena. In Medi- The Use of Chemistry in the Art of Pbyfic is sine. obvious ; as it explains the nature both of the
folid and Auid Parts of the Body.--The Author pursues this use thro' all the Parts of Physick, as
Pathology, Semeiotice, Diætetice, and Therapeutice; In the Mo-and proceeds hence to the mechanical Arts, where chanical he thews Chemistry of use in Painting, by the Arts.
Colours which it furnishes; in Enamelling, which is founded wholly on Chemistry ; in the Art of Glass, which is also a chemical Process ; in the Art of Dying, which depends wholly on it, both as to the preparing of the Stuffs for imbibing and retaining the Colours, and the ordering of the Colours themselves; in Painting on Glass, which is wholly performed by chemical Means ; in the Art of making Gems to vye with natural ones, which is performed either by giving the proper Colours to Glafs, or by staining Crystal ; in the Art of Metals, or the working and fitting them for human Ufe, which is a chief Branch of Chemistry. Chemistry is also of use in the Art of War, as managed among
the Moderns, which depends on Gunpowder a In natu- chemical Composition; in Natural Magic, where ral Magic. the usefulness of Chemistry is fcrupulously pursued by the Author into a long detail of par