Page:Cyclopaedia, Chambers - Volume 2.djvu/188

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MET

(U* )

MET

cile Principles requir'd for the Formation ol Iron: fo that, according to all Appearances, 'tis an Affemblage of thofe Sulphurs, Salts and Earth in the Oil, that the Iron is form'd by Calcination j and therefore that the Means ufed to the Iron in the Ingredients, are the very fame with thofe by which it is compos'd.

Hence it appears, that vegetable Matters contain the Principles of Minerals. But Ni.Geoffroy goes further: and to fupport his Doctrine of the Production of Metals, un- dertakes to prove, that the Principles of Vegetables, and thofe of Minerals, are eJTentially the fame j and that one may readily, and with eafe, decompound Minerals, by feparating their Principles, and compound 'em again, by fubftituting Principles taken from Vegetables in lieu of thofe taken away.

To clear this Point, he examines and compares the Principles of Mineral and Vegetable Salts. The Princi- pal in the Mineral Clafs, are Nitre, Sea-Salt, and Vitriol : All which Salts we find in Plants. On the other hand, the effential Salt of the Par'tetaria is wholly nitrous, and melts on the Coals like Salt- Petre. The flx'd Salts of the Cardans BensdiBus, Jbfinthium, Kali, £-?c. contain a great deal of Sea-Salt, which cryftallizes in Cubes, and precipitates on the Coals. Add, that the greatest part of the fix'd Salts of Plants calcin'd to a certain degree, yield a ftrong Smell of Sulphur, which can proceed from nothing but a vitri- olic Salt, rarify'd and volatilized by the Oil of the Plant. By thefe Salts we may be able to judge of all the other Salts of Plants j for the volatile Silts are nothing elte but fix'd Salts difengag'd from the groffeft part of their Earth, and join'd with parts of Oil. See Salt.

Further, there is fcarcs any reafon to doubt, that the acid Juices drawn from Vegetables, are of the fame nature with the mineral Acids; with this only difference, that the Acids of Plants have i-been extremely rarify'd by Fer- mentation, and united fo clofely with Sulphurs, that 'tis not without a great deal of difficulty that they are fepa- rated.

Thus, diflill'd Vinegar, which we make no fcruple of ranking among the vitriolic Acids j does only differ from Spirit of Sulphur, Spirit of Vitriol, or even the Cauftic Oil of Vitriol, in that the Acids in the Vinegar are dif- fufed among a great deal of Phlegm, and ftrongly united to a great deal of Oil, which yet may be feparated. By diffolving Copper in the Acid of Vinegar, feparated, as much as poflible from its Oil, there are form'd Cry- ftals, like in figure to thofe of blue Vitriol. From all which it appears, that the Salts of Plants do not differ ef- fentiallyfrom thofe of Minerals.

For Sulphurs, the inflammable or fulphureous Principle is the fame in Vegetables as in Minerals. And M. Geoff ray even /hews, that the Principle of inflammability in com- mon Sulphur, is the fame with that which renders the Fat of Animals, the Oils and Refins of Plants, and the Bitu- mens of the Earth, inflammable. To which he adds, that this fame fulphureous Principle is not only likewife found in metallic Subitances, but that 'tis this which gives them their Fufibility, Ductility, and metallic Forms. Thus Antimony, which is a Subitance approaching the neareftof any to a Metal, is little elfe but a burning Sulphur. By exhaling this, it lofes its metallick Form, and becomes a kind of grey Afhcs, which being melted, inftead of Metal becomes Glafs. By melting this over again, and adding to it fome inflammable Matter, as Tartar, it returns into a Regulus.

As to the Species of Metals, there are four which the Chymifts call ImperfeB t becaufe their Principles are not bound fo fall together, but that the Force of a common Fire deftroys them; thefe are, Iron, Copper, Lead and Tin : the others, which are Proof againft common Fire, are Gold and Silver. In the four firft 'tis eafy- to fee the Principle of Inflammability. They become all fufible by the Ad- dition of Salt-Petre, cither in a greater or lefs degree. I- ronis that wherein this is the raoft vilible j next, Tin; then Copper and Lead. But the Principle is more confpicuous ftill, in the Duft or fmall Filings of the Metals, let fall in the Flame of a Candle, than in the Lump. For Gold and Silver, the fulphurous Principle is not fo obvious. No Heat but that of the Sun collected into a Focus, is capable to decompound rhem. But no doubt they have the fame Principles with the other Metal;, tho' not fo ea- fily feen. In Gold, as well as in the imperfect Metals, the Ground is an Earth capable of Vitrification, as ap- pears by the Glafs remaining after the Calcination of Gold in a Burning-GIafs; and there is reafon to believe, that the greateft part of what is exhaled in Smoak during the Operation, is the fulphurous Principle mix'd with Salts. As to Silver, there is fometbing in it extremely various. When purify 'd with Antimony, ir vitrifies in the Sun; but if purify'd with Lead, it leaves nothing behind it but grey A/hes. The Ground of this Metal is doubtlefs an Earth capable of Vitrification; and what exhales in

Smoak, is apparently a Mixture of Sulphur, Salts, and a little Earth volatilized by the Fire. See Sulphur.

From all which,and many more Obfervaticns of the fame kind, U.Geoffroy ventures to draw thefollowing Conclufums. lhat the Subitances whereof Metals are eompoj&dl don't differ effentially from thofe which compote Vegetables, lhat the imperfefl Metals are compoted of a Sulphur vitriolic Salt, and a verifiable Earth, That this fulphu- rous Principle is more or lefs ftrongly join'd with the o- ther Principles 5 very ilrongly in Gold and in Silver, lefs in Antimony, and very little in mineral Sulphur. That the Principle of Inflammability may be feparated from metallick Subftances, either by culinary Fire, or by the Sun. That the Metal thus def'poiled of its Principle is converted into A/hes. That thefe Arties, purfued farther with a violent Fire, vitrify; and that thefe AJhcs, or ra- ™ er P Ia %' by the application of fome inflammable Matter, refume the metallic Form they had loll. That 'tis by this means Linfeed-OH turns Argilla into Iron. That if we knew all the other metallic Earths, they miaht likewife be immediately converted into Metals, by?he Projection of fome inflammable Marter. That 'tis the feline and earthy Parrs, found in Oil of Vitriol, that fur- ni/h the Earth capable of Vitrification, which makes the Bate or Ground of Iron, and receives the metallic Form from the fulphurous Principle of the Oil. That the Iron found in the A/hes of Plants, was produced rhere in the fame manner : And, That 'tis a Compofition of the veri- fiable Earth of the Plants, the Acid of thofe Plants, and their oily or inflammable Principle.

_> The fame Author, the better toafcemin the conftituent Parts of Metals, made a great number of Experiments on them with the Duke of Orleans's large Burning-GIafs j the Refult whereof falls in with, and confirms the Doc- trine laid down above.

From thofe Experiments, he fays, it appears, That the four Metals which we call imferfeB, viz. Iron, Copper Tin and Lead, are compofed of a Sulphur or'oilySuh- ftance, capable of Inflammation, and a metallic Earth capable of Vitrification. That from this Sulphur proceed the Opacity, Brightnefs and Malleability of a Metal. That this metallic Sulphur does not appear at all different from the Oil or Sulphur of Vegetables, or even Animals; and that it is the fame in Mercury as in the four imper- fect Metals. That thefe four Metalshavc f or the ir Balis an Earth fufceptible of Vitrification 3 that this Earth is different in each of the four Metals, in that it vitrifies differently in each; and that on this Difference in vitrify- ing, depends the Difference of Metals. Sec Vitrifica- tion.

The excellent Eoerhaave, after an accurate Survey of the feveral Metals, their Characters, Properties, Prepara- tions, Ufes, gfff. draws the following Corollaries concern- ing the general Nature of Metals.

1. That which dittinguifhes Metals from all other Bo- dies, as well as from each other, is their Heavinefs : Tho every Metal has its peculiar Weight 5 which no Art is able to imitate, and which depends, as Hetmont and the Chy- mifts exprefs it, on the Anatic Homogeneity of the Parts. Now* the later Philofophers have proved, that all corpo- real Magnitude has juii fo much reality in ir, as Weight » and therefore if you have found the Heavinefs of any Metal, you have at the fame time found its Corporeity. Sir If. Newton treating of Gravin, , and Huy^ens of the Pendulum, fliew that Weight and Reality are correfpon- dent. See Weight and Gravity.

2. The Metals appear to be Simple, yet are really Com- pounds. Their component Principles, according to the Antients, are Sulphur and Mercury; to which Yome of the Moderns have added Salt : but 'tis certain Salt is no conftituent Parr, or Ingredient of Metals, but rather fome- thing external adhering to them. All Metals con fill of two Parts, or Principles; Mercury as the Bails or Matter; and Sulphur as the Binder or Cement : the firft, the Sub- ftratum, or metallic. Matter j and the fecund, that which renders it fix'd and malleable. The Mercurv, it is to be noted, is the fame with ourQuickfilver, only defecate and clear of any heterogeneous Matter 3 whereas the common Quickfilver is always mix'd. As to the Sulphur, it is not the vulgar foflU Sulphur, but a peculiar fore of Matter fpecifically denominated Sulphur of Metals, concluded by fome of our lateft, and beft Chymifts, particularly Motif. Bomber*, to be Fire j which being mix'd with the Mcr= cury, fixes it, and according to the different decrees of its Union and Cohefion therewith, produces different ivJe- tals. See Mercury, Sulphur, Fire, fj$c r

This Doctrine of the Compofuion of MetaJs is confirmed by an Experiment of Mr. Boyle, who after having retain'd Mercury a long time in a moderate fire, took a piece of Gold out of it, which J tv as apparent was not in the Mer- cury before it was expofed to the Fire. Monf. Hnmberr's Experiment is to the fame effect; from which he con-

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