Page:Cyclopaedia, Chambers - Volume 2.djvu/187

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MET

meafure to the Hammer; but then they fell to Duft in the Fite: And lb of the rcll. S;e Malleability, i$c.

We find but fix Metals in all Nature, ss'JB. Cold, Lead, Silver, Cupper, Iron, cad Tin. See the Mature, Charafters, Produaion, L'fes, lie of each thereof, under its proper Article; Gold, Leap, Silver, Copper Tin.

To thefe, afeventh Metal is ufually added, viz,. Mer- cury, or Quicksilver ; but improperly, as it has not all the Characters of a Metal, nor karce any thing in com- mon with the other Metals, except Weight and Similarity of parts. See Mercury, £fc _

Thus, for Example, it is neither diffolvable by lire, malleable, nor fix'd : In effefl, it feems to conlhtute a peculiar Clafs of Foffils, and is rather the Mother, or Balis of all Metals, than a Metal idelf. However, as it is uiually reckoned among them, and as it wants nothing to render it a Metal, but an additional Sulphur to fix and connect its parts together, it may without any great harm be cun- fidcr'd under that Clafs.

The common radical Character of Metals is, that of all known Bodies, they are the heavier!. By Dr. HaUy's. Ex- periments, the Weight of Gold to that of Glafs is deter- mined to be as 7 to i ; and the Weight of Tin, the lighted of all Metals, to ihit of Gold, as 7 to 15) ; which considerably furpaffes the Weight of all Stones, Marbles, Gems, and other the mofl folid Bodies, as appears from the Tables of fpecific Gravities. Nor is there any Body in Nature but a Metal, that is one third of the Weight of Gold. See Specific Gravity.

The Royal Society furnilh us with various Experiments of this kind. The Weights of the feveral Metals, and other Solids, they have examined Hydroltatically, by weighing them in Air and in Water ; and the Weights of the Fluids by weighing an equal Portion of each. By fuch Experiments they find, that taking the fame Weights of Water and Gold, the Bulk or Magnitude of the former is to the latter as 19636 to loco ; confequently that the Weight of Gold is to Water nearly as 19 to 1.

The Specific Weight of the feveral Metals by this Means determined, fland thus :

( S40 ) MET

the one at liberty from the other ; the Moiflure evapo- rates, and the Earth is redue'd into Scoria's, £«fc.

J)X. Woodward accounts tor the Production ot Metals found in the Earth, in the following manner.

All M&aU now found in the Strata owe their prefenc Condition to the Deluge j when, alio he imagines the Strata Iron, and of Stone, Earth, Marble, &c. were form'd. See De- luge.

The Metallic and Mineral Matter now fourd in the per- pendicular Intervals or Fiflure's of the feveral Strata, whereof the Body of the Earth is compos'd, was, accor- ding to him, at the time of the Deluge lodg'd in the Bodies uf thofe Strata, anil brought thence, and tianfmitred into thefe Intervals fince that times the Intervals them- felve-s not exifttng, till the Strata were form'd and broke again, to let the Water from the Earth.

Now the Water which, he imagines, is conflantly af- cending from the Abyfs (fee Abyss) towards the Surface of the Earth; continually pervading the Strata, detaches out of their Pores and InterRices fuch Metallic znA Mineral Corpufdcs as it finds loofe in its way, carrying them along with it to the perpendicular Intervals, where having

freer Paffag'e than before, ir deferts them, and leaves

And this he takes to be the

1 thofe Places, were

Gold 19S35

Iron

7852

Quick-Silver 14019

Tin

73 = i

Lead 11341

Stone

2000

Silver 105135

Water

1000

Copper 884;

Air

JL

The Culic Inch 0/ V 'f C

unces. Drams.

Grains

Gold

12

2

i*

Quick-Silver

8

6

8

Lead '{•§, Silver CS"

7 5

3 5

30 28

Copper I ?

5

<r

3<

Iron 1 !

5

1

24

Tin j.

v

4

6

17

As to the Origin and Formation of Metals, various are the Sentiments of Philofophers Antient and Modern.

Plato will have the Caufe of Metals to be a humid Va- pour, inclofed in the Bowels of the Earth, which being varioufiy internaix'd with Parts of the Earth, produce various Metals. Flotin will have Sulphur to be the Father of Metals; and an oleaginous vifcous Humour the Mother. Lidyat endeavours to prove all MltdU generated by- a fubter- ranean Fire ; urging, among other Reafons, that many Metah, when taken out of the Earth, are exceedingly hot. V11 Hamel fhews, that Metals don't take their Rife either from any vaporous Exhalation, or from Water, or from Earth 5 but are generated of Mercury, Sulphur and Salt. He adds, that Metals take their Matter and Weight from the Mercury, and their Tin&ure and Form from Sulphur.

The fame Author owns the firft Rudiment of a Metal to be a faiine Subftance fwimming inWater, which is by little and little carry'd off". By how much the Terreftrial Parts are more exquifitely mix'd with the aqueous or humid, by fo much is the Metal more heavy and firm, as having fewer and fmaller Pores. Hence its Ductility 5 for its Parts be- ing extremely fmall, denfe, and complicated, may be drawn out into a very fpacious Surface. On which account it is, that Gold exceeds all other Metals both in Weight and Ductility ; hence alfo its Fixity, its Parts being too clofe and denfe to be exhaled. The Water defends the Earth from being burnt, and the Earth the Water from flying off ; neither for fakes the other, but each is bound in an undiflolvable Knot. The Moiflure gives Ductility, the Earth Solidity. Where the Mixture is lefs perfect, whether the Earth or the Water prevail, the Metal will neither have fo much Weight, as having larger Pores 5 nor will it bear the Fire fo well. For if the Earth pre- vail, as in Iron, or the Water, as in Lead 5 Heat will fet

them in thofe Intervals.

way in which sliM&als, now found i

brought thither, and ftill grow.

Thofe in the Strata, however, he obferves do not, nor cannot grow '■> but, on the contrary, are continually lcflen'tl and diminilh'd, by fo much as has been convey'd into the perpendicular Intervals, and brought forth of the Surface of the Earth by Springs and Exhalations from the Abyfs, &c. See Fossil.

The fame ingenious Author complains of the great Uncertainty and Inconflancy in the Mineral and Metallic Kingdom -■, neither Colour, Figure, nor Situation in the Earth, being to be depended on, fo as to make any pofiuve Judgment from them. A Pyrites or Marcha- fite, for inflance, iliall have the Colour and Brightnefs of Gold and Silver, and yet afford nothing but a little Vi~ triol and Sulphur 5 while a Pebble in appearance iliall have a Mixture of a valuable Metal in it. 'Tis common too to find the fame Metal fhot into a great number of different Forms, as well as to find different Kinds of Metal of the fame Form. And as to their Place in the Earth, there is the fame Uncertainty, being fometimes found in the perpendicular Fiffures or Intervals of the Strata, fometimes interfperfed in the Bodies of the Strata, and fometimes in both. The fame Metals are alfo placed indifferently in all kind of terreftrial Metal, or in Strata of very different natures. They are frequently intermixed with each other, fo *hat 'tis a rare thing to find any of them pure and fimple j but Copper and Iron frail be in the fame Mafs, Gold and Copper, Silver and Lead, Tin and Lead; nay, fometimes ail fix together in the fame Lump. See Mineral.

M. Tourjiefort is of opinion, that all Metals have their Origin from Seeds, like Plants, ; that they have Veffels, with Juices circulating in them, £S?c.

The French Chymifts have been very curious in their Inquiries into the Nature and Production of Metals.

M..GeoJfroy, from a Mixture of Sulphur with a vitriolic Salt, and an argillous Earth, brought an Iron, which he maintiin'd to be a new Production, or a Compofition refulting from the Affeinblage of certain Principles, which exilled feparately in the Ingredients that formed the Me- tal 5 in a word, that it was an artificial Iron. And obfer- ving that there were Parcels of this Metal in the coloured Allies of Plants, and of moft other inflammable Sub- fiances, he concluded that it might be form'd there alfo by the Union of the fame three Principles.

This was oppos'd by M. Lemery the younger, who maintain'd that the Iron conrain'd in the Afhes of Plants, was not form'd there by Calcination, but was really ex- igent in the Plants themfelves, being rais'd in their Veffels along with the Juices of the Earth ; and further, that all the Ingredients whereof M. Geojfroy's artificial Iron were form'd, do really contain Iron in themfetves, either in fmaller or larger Quantities : Not the Argilla only, where the Iron iseaiily difcover'd by an animated Knife ; nor the Oil of Vitriol, which is drawn from a Mineral, the Ground whereof is Iron j but alfo Linfeed Oil, where- of M. Geoffroy's, Sulphur was made 5 and even that of Turpentine, fweet Almonds, £sV. relating withal the Ope- rations whereby each of thofe Oils might be redue'd to an Earth wherein was Iron.

To this it is anfwer'd, that in what manner foever Iron be drawn from the feveral Ingredients feparately, there will be ftill found infinitely lefs in 'em, than when mix'd, and that of confequence the Mixture produces Iron. That as for Oils, 'tis evident they are not fimple Sub- ftances, but are compos'd of an Earth, an acid and a ful- phurous or inflammable Part j which are the three pre-

cife