CHYMICAL DISCEPTATIONS; Or, SOME DISCOURSES UPON Acid and Alkali.

DEar Pyrophilus, We shall at last arrive at the End of our Errors, and Draw from the Fountain of Nature it self, Those Necessary Lights which can make us Philoso­phers.

What say you, Eu­bulus?

I say nothing but what I can convince you of by evi­dent Reason and certain Expe­riments.

How have you discove­red the Truth?

The Reading good Au­thors, and the Converse which I, for some time, have had with learned Men, have quite demo­lished all my Prejudices, and made me Examine things with as much Freedom and Imparti­ality, as I had before of Anti­pathy: I have constantly ob­served, That Authority, eve [...] to this present time, hath been an Invincible Enemy both to Physick and Medicine, and the very Rock upon which all the Famous Men of the past Ages have rely'd; and is indeed, at [Page 3]this day, the Cause of so ma­ny Sects and different Opinions which we see in the Schools: Whereas Reason and Experi­ence are the only True KEYS which can give Admittance in­ [...]o either of these Sciences: for, [...]o be a Philosopher, it is abso­ [...]utely necessary to banish Au­ [...]hority, and to follow Reason [...]nd Experience. I am not [...]ble sufficiently to admire the [...]rosperous Success and Exact­ [...]ess of the Anatomists and Chy­ [...]ists of our Age! The first [...]aving discovered to us, in the Body, Parts, Humours and Uses [...]nknown to the Antients: and [...]he Last have withdrawn us [...]rom that erroneous Darkness wherein the Four Elements and [...]heir First and Occult Qualities [Page 4]had plunged us, giving us Prin­ciples as clear as those were ob­scure.

I have alwaies told you That Anatomy and Chymistry were great Assistants to Physick and Medicine, and that they en­lighten us much, where we at­tain it only by their Experi­ments.

I do not design to En­tertain you here with the New Discoveries of Anatomists upon Humane Bodies: I shall only speak of those which Chy­mists have made us take No­tice of, in the Dissolution of Mixts. Know, that for this Effect, They acknowledg two sorts of Principles; of which, some they call Active Princi­ples; and others they stile Pas­sive [Page 5]Principles. The Active Prin­ [...]iples are the Causes of all the Actions and all the different Motions which are done in Nature: The Passive Princi­ [...]les, on the contrary, are not [...]apable of any Action, but serve only as Matrixes to the active Principles for them therein to make their Productions.

VVe cannot desire an exacter Distinction of Princi­ples, but how many have you of either.

There is some Contro­versy amongst Chymists about the Number of Active Princi­ples; Some will have Three, which they call Salt, Sulphur and Mercury; pretending that these are the last Bodies they [Page 6]find in the Resolution of Mixts. By Mercury they understand the most subtile, most penetra­ting and most aetherial Sub­stance in the Mixt. By Sul­phur, all that which is there­in oleagenous and inflamable and, By Salt, and that is dissol­ved in Water, and coagulated by Fire: they say, The Mer­cury or Spirit is the Soul of Bo­dies, That it gives Motion and Life to Animals, That it makes Plants grow, brings forth blow­ers, and ripens Fruits; also that it renders Stones and Met­tals perfect. That the Sulphur or Oil Causes the Diversity of Colours and Odors, the Beau­ty and Deformity of Bodies: and, That the Salt is the cause of the Tastes, Weight, Solidi­ty, [Page 7]and hardness of Mixts. Others acknowledg that there are Salt, Sulphur and Mercury in all Bodies; they demonstrate also by several Experiments, That these Three Substances are composed of Two others, a great deal more simple, viz. of Acid and Alkali Salts, and that Salt, Sulphur and Mercury are no other but these Two Salts at liberty or intangl'd: In effect, you shall observe, That there are Two sorts of Salts, there are some Simples, which are not compounded of any other Sub­stance; and some Compounds (as are all the compound Mi­neral Salts, and essential Salts of Plants) which are composed of simple Salts and passive Principles, notwithstanding in [Page 6] [...] [Page 7] [...] [Page 8]such sort as the Acid, which is the first of these simple Salts, predominates therein. And these Salts are called Salts, be­cause they are dissolved by Moi­sture, and coagulated by Dri­ness.

The simple Salts are either Alkali or Acid; the Alkali Salts are either Fixed or Volatile: the Acid Salts are alwaies in a Liquor; therefore called Acid Spirits: nevertheless, these A­cid Spirits are no other but A­cid Salts dissolved in a little water. The Alkali Salt, on the contrary, is almost alwaies in a Body: it is, as I said but even now, either fixed or vola­tile: the fixed Alkali Salt is never elevated by the action of Fire, as Salt of Tartar, and [Page 9]all those Salts which are drawn from Plants by Incineration, which we call Lixiviate Salts, as those of Scordium, Tama­risk, &c. The Volatile Alkali Salt, on the contrary, is eleva­ted with the least heat of fire, and is drawn chiefly from Ani­mals, as the Volatile Salt of Vi­pers, Harts, &c.

There are Three Sorts of Mercury or Spirit; an Acid Spi­rit, as that of Niter, Allum, Vitriol, &c. A sharp or biting Spirit, as that of Harts-horn. Urine, Vipers, &c. and a bur­ning Spirit, as that of Wine, Beer, Cyder, &c. The Acid Spirit is an Acid Salt dissolved in a little Flegm: The sharp biting Spirit is an Alkali, vola­tile likewise, dissolved in a little [Page 10]Flegm and the burning Spirit is a Sulphur; and a Sulphur is an enveloped Acid.

All Chymists, in effect, agree That there are two passive Prin­ciples, viz. Water and Earth, or Flegm and Caput Mort.

The Water serves as a Men­struum and Dissolvant to the Acid and Alkali Salts; and it is extracted by Distillation from those Bodies which contain it.

The Earth serves as a Bond to these Two Salts, it is extra­cted commonly after the Ex­traction of the Lixivious Salt.

It is to be noted, That accor­ding to the different Mixture of these Four sorts of Substan­ces, and the different Rangings of their Parts, there are made different Productions in Nature, [Page 11]sometimes of Animals, some­times of Vegetables, and some­times of Minerals.

What do you mean by Acid Salt and Alkali Salt?

The Acid Salt is easily known by the Tast and Smell, and by the Firmentation which it makes with Alkali's, as Spi­rit of Sulphur. This Salt is composed of small sharp poin­ted parts, which insinuate themselves into the Pores of those Bodies they meet with, and make either a Dis-union of their Parts, or a Coagulation: for, according to the different Motions, particular Figure. Sub­tilty or Grosness of these Points and the disposition of those Bo­dies, they either pass through them with Violence, and scat­ter [Page 12]their parts one from ano­ther: or else they are Entang­led therein, in such sort that they lose their Force and their Motion in them: Remaining very often sticking to them.

We observe, in effect, That Acid Salts dissolve hard Bodies, as Stones, and Metals, (except Gold, which cannot be dissolv'd but in salt Menstruums:) and coagulates the most part of soft and fluid Bodies, such as Milk, Blood. &c.

Then, there are Acid Salts of different Natures?

There are as many dif­ferent sorts of Acid salts as there are different Bodies in Na­ture; and though the Particles or Attoms which compose them are all sharp, yet that hinders [Page 13]not, but they have neverthe­less all different Figures, which causes all the compound Mine­ral Salts, in which the Acid salt predominates, as Niter, Vi­triol, &c. and also the Essenti­al Salts of Plants, to take all different Figures in their Coa­gulations according to the Na­ture of the Acid which deter­mines them, whence some are formed Pyramidical, as Niter; others, winding like a Screw, as Vitriol, &c.

Whence comes it, That Acids dissolve Silver and other Metals, and do not dissolve Gold? and, on the contrary, salt Liquors dissolve Gold, and touch neither Silver nor other Metals?

Gold being almost all [Page 14]Sulphur, cannot be corroded by Acids of what nature soever they be, it must be salt Liquor, and as perfect a Spirit of Salt as can dissolve; which in Cor­rosion must re-take the Nature of Salt: Silver and other Metals having, on the contrary, more Mercury than Sulphur, can ne­ver be dissolved in salt Menstru­ums, for there is none but Acid Spirits that can dissolve them. To confirm both to you, You ought to take Notice, That those that work in Slat Petar, after they have extracted it, draw forth yet a Salt, a great deal less acid; which is of the Nature of common salt, which they call Sal centrique, which when it is Resolved into a Li­quor dissolves Gold after the [Page 15]same Manner as Spirit of Salt doth, and in corroding re-takes the Nature of Salt, and dissolves neither Silver nor other Me­tals.

Suppose that Gold be almost all Sulphur, and then it is easy to comprehend, Why it cannot be dissolved by Acids, but only by salt Menstruums.

Have you never obser­ved, That when Gold is in flux, if the end of an iron Rod be put therein, it will be calcined and reduced into Scoria? after the same manner as if it had been burnt with common Sulphur: and, that Argent vive forsakes all Metals to join it self with Gold, which it renders as brit­tle as Glass: How should Gold calcine Iron, and be in such wise [Page 16]penetrated by Mercury, as to become brittle as Glass, if it did not abound with Sulphur? first you know, That Iron can't be calcin'd but by Sulphur, which seeing Gold calcines, conse­quently Gold must be a Sul­phur. Secondly, Mercury be­ing a powerful Metallick Alka­li (though imprisoned) which is not joined but with a Sul­phur of its own Nature, would not quit other Metals to be joi­ned to Gold, if Gold had not more Sulphur than others: and the Mercury renders it not o­therwise brittle, but because it absorbs its Sulphur and dis-u­nites the parts thereof.

Mercury, nevertheless, does not destroy the Body of Gold, which it would do, if it [Page 17]absorbed the Sulphur, and dis­united the parts thereof.

That is not a Conse­quence, That because the Mer­cury absorbed the Sulphur of Gold, and scattered the parts thereof, It must therefore de­stroy it; for the Sulphur of Gold being most fixed, and the Mercury, on the contrary, be­ing most volatile, there cannot be made an exact Union betwixt them two, that is to say, by small parts; and, the Mercury being cast into the fire, quits in that moment the Sulphur of the Gold which it had absor­bed, and flies away, and the Sulphur of the Gold is re-uni­ted to its own Mercury, and the Gold becomes as hard, as fixed and as solid as it was before: [Page 18]Moreover, how should Gold be­come fulminant, if it did not a­bound in Sulphur? The com­position of Aurum fulminans makes us sufficiently sensible of it. They cause Gold to dissolve in Aqua Regis, which they af­terwards precipitate by little and little with Oil of Tartar made per Deliquium: there is then made a Union of the Al­kali of Tartar with the Acid spirit of the Nitar, which com­posed the Aqua fort; and there is produced therefrom a new­made Nitar: this Nitar, being united to the Sulphur of the Gold, is inflamed, and produ­ceth all those surprizing Effects which we take Notice of there­in.

The Nitar would Pro­duce [Page 19]these Effects alone, or be­ing mingled with the Sal Armo­niack or common Salt, which was put into the Aqua Regia.

Salt-Petar is never in­flamed but when it is mingled with some Sulphur; as with common Sulphur in Gun-pou­der and Pulvis fulminans; or with the Sulphur of Antimony when one makes Regulus and Liver, &c. Common salt and Sal Armoniack are so far from rend'ring Salt-Petar inflamable, that they extinguish fire with more force than common Wa­ter doth: it therefore follows, That the Sulphur of the Gold is united with the Salt-Petar, and causes this Deflagration.

We see never [...]less, That Salt-Petar is inflamed at [Page 20]the same time that one puts it on burning Coals.

The Salt Petar is not inflamed then, but because it is united to the Sulphur of the Coals: for if one put some Salt-Petar into a Crucible and make the Crucible red-hot, it simply melts, and is not inflamed but when one casts some Sulphur or some Coal thereinto.

And, to convince you fully, That Gold contains a great deal more Sulphur than other Me­tals; You may take Notice, That one cannot make either Silver, Lead or Tin fulminant, because These Metals have on­ly a very little Sulphur, which is wholy absorbed by their Mer­cury.

There is nothing in the [Page 21]world which ows not its Birth to Acid Salt: nothing can live, nor be multiplied without it: It is that Soul of the World, of which the Antients have so of­ten told us:

The Spirit within, and the Mind infused, through the Members nourisheth and agi­tates the whole Body.

In a word, The Acid Salt is the Author of the Construction of every Body, and the abso­lute Master of Alkali Salts, it prints them (as a Seal is made on Wax) with all sorts of Cha­racters, and makes thereof se­veral different Bodies, accord­ing [Page 22]to the diversity of its points, as we observe by the Regeneration of the Essential Salts of Plants, and compound Mineral Salts.

If one mingles with an Alkali, either fixed or volatile, the A­cid Liquor of some Vegetable: as for example, Of the grains of Kermes, or Wine, 'till there is not made any more Fermenta­tion, and then one philters them through grey Paper, and evaporates the superfluous hu­midity, causing them to cristal­lize in a Cellar or some other cool place: there will be made thereof an essential Salt of Ker­mes, which hath the same Vir­tues with that which is ordina­rily drawn. There will also be made a Tartar like that of [Page 23]Wine, whose, sourness is gone.

The Acid Spirits of com­pound Mineral Salts, as of Al­lum, Niter, &c. change all sorts of Alkali's into Salts of their own nature, to wit, into Alum, Niter, &c. like to those from which they were drawn.

These Experiments are most fine, most curious and most convincing, & this new way of Reasoning by Deeds, please me much: but pray give me as clear an Idea of Alkali Salt, as this you have giv'n me of Acid Salt.

The Alkali Salt is ea­sily known, by its fermentati­on with Acids, and by its pre­cipitating Vitriol of Mars, and other compound Mineral Salts dissolved in water, except Sea salt, in which, the Acid and [Page 24]Alkali are so strictly united that neither the violence of fire, nor the mixture of any other Body can ever dis-unite them, as I have already said, where I spoke of the Dissoluti­on of Gold in salt Menstruums. I have caused you to take No­tice, That there are two sorts of Alkali's, a fixed and a vola­tile; fixed, as Salt of Tartar: Volatile, as the volatile Salt of Vipers.

Sal Alkali is extreamly po­rous, wholy empty and rough, that is to say, whose parts are unequal: and, 'tis for this Rea­son, That it whitens Linnen, and cleanseth Stuffs: It takes out the Filths that are found therein by its Inequalities, and it fills at length its pores there­with.

What Proofs have you That Sal Alkali is vacuous and cleanses Linnen and Stuffs.

There are several Ex­periments which proove both. If Alkali's were not vacuous Salts, How should they be so easily resolved into in Liquor, when they are put into a moist place? since 'tis observed that Salts filled with their Acids, as Niter, Alumn, Vitriol, &c. are not Dissolv'd therein; the Al­kali of Niter, which has not been separated from its Caput Mort. could not charge it self with an Acid equal to that which was drawn therefrom: Diaphoretick Antimony which has not yet been washed, should not augment Weight therin, and should not change its Diapho­retick [Page 26]retick quality into an Emetick: in a word, Corals, Lead, and divers other Alkali's reverbera­ted in a violent fire during some daies and nights, should not augment a fifth part; and of Al­kali's as they were, should not become salt, and should ferment still with Acids, as they did be­before, if Alkali's were not va­cuous salts, which are easily fil­led with the Acids of the air and fire. We see, notwithstan­ding all these Experiments are true: that the Alkali of Nitar draws out of the Air an Acid of its own Nature, That Antimo­nium Diaphoreticum becomes therein Emetick: that reverbe­rated Corals augment not only in weight, but also become Salt, and ferment no more with [Page 27]Acids, from whence we may very justly conclude, That Al­cali Salts are vacuous and po­rous Salts, which fill them­selves with all sorts of Acids, of what nature soever they may be.

There are also no less Proofs that Sal Alkali whitens Linnen and cleanseth stuffs: if you have observed, that one cannot make a Lixivium of ashes wherein this salt is wanting, as it is in those of Wood, which hath a long time floated, but only of those in which it abounds, as in the ashes of Oaks, Apple­tree, Broom, &c. and, That the salt Salts, as common Salt, can never cleanse them, because that their Alkali is wholy fil­led with its Acid, and so con­sequently [Page 28]it cannot fill it self with the filths of the Linnen and Stuffs: I should have no need to bring any other proofs, nor to tell you, That the herb which we call Saponaire [Soap­wort] because it is made use of to whiten Linnen and Stuffs, cleanses them on no other ac­count, but because it abounds in this Salt.

I am sufficiently convin­ced by what you have told me. You have already explain'd (where you spoke of the Disso­lution of Metals) why Gold cannot be dissolved but by a Salt Liquor, and Silver and the other Metals, on the contrary, but by an Acid Liquor: I would willingly you Explained to me, Why Acids do not precipitate [Page 29]Vitriol of Mars dissolv'd in wa­ter, as Alkali's do: and, as they, on the contrary, precipi­tate equal with them, Mercury sublimate dissolved in common water, & ☿ dissolv'd in Aq. fort.

It is easy to give you a Reason for all these different Ef­fects: for, Little do you consi­der the manner by which these Praecipitations are performed. Alkali's, as well fixed as vola­tile precipitate all these Disso­lutions, because they absorb the Acids which hold the Iron and Mercury in Dissolution; and in this Manner the Iron and the Mercury being no longer detai­ned nor agitated by the points of those Acids, are precipitated and fall by their own weight to the bottom of the Vessel [Page 30]which contains them: It hap­pens much otherwise in the precipitation which Acids make of corrosive sublimate dissolv'd in common Water, and Mercu­ry dissolved in Aqua fort. for there is not made any Union of Acid with Alkali, but only a Confusion of Acid with Acid: and this precipitation happens only because the Acids of Ni­ter, Vitriol and common salt which had sublimed the Mer­cury, and those of the Aqua fort. which had dissolv'd it, were not able to penetrate, nor unite themselves intimately with it: which causes that a new Acid easily shakes them & makes them at the same time to quit their hold; thus is the ☿ precipitated: This is the Rea­son [Page 31]why Acids can never preci­pitate Vitriol of Mars dissolv'd in water, because there is so perfect and strict a Union be­tween its Acid and Alkali, that there is not found the least pore which is not filled, in such man­ner, That a New Acid not fin­ding therein any vacuous place can never dis-unite them.

I do not yet well under­stand how Acids which hold a Body in Dissolution, can quit it to join themselves to another.

Experience will present­ly make you comprehend it, for if one casts upon a Solution of Vitriol of Mars and upon that of Mercury sublimate an Alkali, whatsoever it be, there will be made at that instant a Precipitate: and, if after ha­ving [Page 32]put an Alkali to it, there is immediately put, an Acid, there will not be made any pre­cipitate, but the solution will remain as clear as it was be­fore; because the Acid which was put last thereto, joining it self to the Alkali which was put to it before, hinders con­quently that that Alkali can­not absorb the Acid which held the Mercury and Iron in disso­tion: if this Precipitation of Vitriol or Mars, and Mercury dissolved by Acid Spirits and precipitated afterwards with Alkali's, was made after any other manner than that which I have already told you, it should be all one whether one put an Acid thereto after there was an Alcali cast into it; or, [Page 33]that one put none, the which notwithstanding happens not, for the Acid which was put thereto, joining it self to the Alkali which was put thereto before, hinders by that means that the Alkali could not ab­sorb the Acid spirits, which held the Mercury and Iron in disiolution.

All your Experiments convince me strongly of that which you have told me concerning Acid and Alkali Salts; but, as it is not suffici­ent to Establish Principles, on­ly to tell what they are, and what they do: It is therefore very needful it be proov'd that they Exist, that they are found in all Bodies, and that they are Principles therto, that's to say, [Page 34]That all Bodies are resolv'd in­to them; and, that they are not resolv'd into any other substance: and, 'Tis this that I could wish you would plainly shew me, concerning these two Salts, if it be possible.

You have none but Animals, Vegetables and Mi­nerals to examine, and you shall not find one of them, in which these two Salts are not to be met withal, and in which they are not Principles.

The Volatile Alkali's which are drawn in abundance from the Blood, Flesh, Horns and Bones of Animals, which fer­ments with all Acids, and pre­cipitates Vitriol of Mars dissol­ved in water, do they not prove, There is excess of Alkali [Page 35]therein? and the different Acid Juices which are separated from their Bodies, as Spittle which mortifies Mercury, it be­ing a powerful Alkali, which cannot be so mortified but by an Acid: and, as the Acid of the Stomach curdles Milk when one drinks it fasting, the which is plainly perceived by Vomit­ing it up again, almost as soon as it was taken, and Milk cannot be coagulated but by an Acid. Flesh, also Blood and Milk which grow sower when they begin to corrupt, prove sufficiently, That there is some Acid Salt in Animals.

Is there a Vegetable in which these two Salts are not found? the simple Fermentation which Vegetable Juices make, should [Page 36]be sufficient to convince you of it; for Fermentation, as I shall tell you hereafter, cannot be made but by the meeting of these two Salts. Also there is not a Vegetable from which we do not draw a great quantity of Alkali, and which does not give, when it begins to corrupt sufficiently sensible signs of its Acidity. How also should we be able to draw an Essential salt from Plants, if they had not Acid and Alkali, seeing Es­sential salts are no other (as I gave you to observe, when I spake of the Regeneration of Salts) than these two Salts joi­ned together.

Do they not draw also an Acid and Alkali from Minerals? compound Mineral Salts, as Vi­triol, [Page 37]Alum, Niter, &c. give us an Acid in dissolution; and leave us an Alkali in the Caput Mort. Calcined stones, as Calx vive, are not fermented when they are dissolved in water; but because they contain each of these two Salts: Hath not com­mon Sulphur its Acid, which they draw, per Campanum, in burning it, and which elevates Mercury into Cinaber? hath it not also its Alkali which re­mains in the Caput Mort? Is there not Acid and Alkali in Antimony, as we observe in the Composition of its Butter? E­qual parts of Antimony and Mercury sublimate they mingle together, which they put in a Retort and commit to the fire. Then the Acid spirits, [Page 38]which had sublimed the Mer­cury, quits it to join it self to the mercurial Part or Alkali of the Antimony, and the Sul­phur or Acid of the Antimony elevates the Mercury into Cin­nabat. Have not the Metals also their Acid and Alkali? Gold abounds in Sulphur which is Acid, and it hath a Mercury which retains this Sulphur, and unites it self inti­mately to it, Silver and the o­ther Metals have a Mercury which ferments with spirit of Niter which is Acid and a Sul­phur which hinders the volati­lity, and fluidity of this Mer­cury.

May not the fire pro­duce these Salts also from the most part of those Bodies from [Page 39]which they are drawn.

No; for when one has once drawn the Salt from A­shes, calcine them never so wel, they will never give others, no more than floted wood [that is. I suppose, Wood that has lain in water till it is rotten] rotten wood, and Plants expo­sed some daies and nights to the Aier, because their salts have been dissolv'd in the air and water, and are consequent­ly drawn out from their Bodies. It should not happen so, if the fire had produced those two Salts; for, then at all times, whether after Putrifaction or Calcination the fire should al­ways, produce some new salt, and one body would give no more than another; the which [Page 40]is contrary to Experien [...]e, as you see.

The Acidity of Blood, Milk and Flesh is natural to them, and those different Acid Juices which we find in the Bodies of Animals are separated there­from without Artifice, and with­out the help of fire.

The Fermentation which Ve­getable Juices make, is done of it self.

In a word; The Acids and Alkali's of compound Mineral salts, separated one from the other by the means of fire, would never recompose the same salts, when one reunites them together, if the Fire had produced them: for, what pro­portion, what relation should these new Productions of the [Page 41]fire have with the Principles which compose these salts, to cause that these Productions should regenerate salts, as natu­ral as Niter, Alum, Sal-gem, &c.

You see plainly by all these Experiments, That the Fire does not produce in Bodies the Salts which we draw there­from, but that these Salts are actually found therein. There remains no more, but that I shew you they are Principles thereto.

There are commonly drawn from all Bodies, three different Substances, to which are given (as I have already said) the names of Salt, Sulphur and Mercury, which are pretended to be the last Bodies, which are [Page 42]found in the Resolution of Mixts: but Experience hath at length discovered, That these Three Substances were compo­sed of Acid Salt and Alkali Salt; and, that these two Salts are not composed of any other sub­stance and by consequence, they ought to be Principles.

For, though the Artist work as much as he will, he may ea­sily find the means to reduce the Salt, Sulphur and Mercury into our Two Salts but he will never find the Knack to reduce these two Salts into any other Substances; and though he make use of the same two In­firnments which he used for the reducing the other Three sub­stances into these Two Salts, to wit, Fire and Water: notwith­standing [Page 43]standing he shall never be able to make that the Acid Salt be no more Acid Salt, nor the Al­kali Salt, Sal Alkali.

I have occasioned you to take Notice, that there are two sorts of Salts, namely, an Acid Salt and an Alkali; That there are Three sorts of Spirits or Mercuries, an Acid spirit, a sharp [biting] spirit, and a bur­ning spirit: that the Acid spi­rit was an Acid Salt, dissolv'd in a little flegm; the sharp spirit a volatile Alkali dissolved also in a little flegm; and the burn­ing spirit, a Sulphur, and Sul­phur an inveloped Acid, I have now no more to do, but to bring you some Experiments to con­vince you of this Truth.

OTHER DISCOƲRSES UPON Acid & Alkali.

THOSE Arguings which we had at our last Meeing have almost wholly persuaded me of the Verity of the Hypothesis of Acid and Alkali: But I must [Page 84]confess, dear EUBULUS, that I have been extreamly shaken by the Reflections of the In­comparable Mr. Boyle upon these Principles, which are lately fallen into my hands, and the Objections which he makes are so strong, that it seems im­possible to bring a solution thereof.

I doubt not but that the Objections which the lear­ed Mr. Boyle makes against Our Hypothesis have much seeming Truth in them; but ne­vertheless, I believe that they may be resolved with great Ease, when one very exactly considers what I have said to you concerning the nature of these two Principles, and all their force will serve to make [Page 85]the Truth of this Hypothesis the more conspicuous.

Mr. Boyle thinks it strange, That they should ex­plain all the Qualities of Bo­dies and the other Phoenome­na's of Nature, by this new System; and, that they attri­bute to it an Extent which ought only to be given to Mat­ter and Motion.

You may easily con­clude by the several Phoenome­na's of all sort of Species which I have explained to you accor­ding to these Principles; That it will be easy to Explain all those which they shall be able to prefer: and I do not see Why the Extent that is given to this Hypothesis, ought to be diffe­rent from that of Matter and [Page 86]Motion, since that in it self is found the Existence of the Mat­ter and Cause of Motion.

Our illustrious English­man pretends, That they have not made Experiments enough, nor sufficient Inductions to prove, That Acid and Alkali are to be found in all Bodies, and in all the sensible Parts of Mixts; and, That they ought not to conclude, that these Two Salts are to be found therein, because such or such Effects are the Emanations of these Princi­ples; as for Example, When the Patrons of Acid and Alkali see Aqua Fort. or Spirit of Ni­ter dissolve Filings of Copper, they conclude thereupon, That the Dissolvant which is Acid, meets, in those filings of Cop­per, [Page 87]with an Alkali upon which it works: Whereas they do not take Notice, That a well deflegm'd Spirit of Urine, which in their Hypothesis is a Vola­tile Alkali, dissolved in a little Flegm, do's dissolve filings of Copper as readily, and much more naturally than Aqua Fort. doth.

I believe you have suf­ficiently proved by those Expe­riments which I brought you, That there is Acid and Alkali in all parts of Mixts. It is most easy to separate these Two Prin­ciples from Animals, Vegeta­bles and the most part of Mine­rals; but as for Metals, These Principles are therein so strict­ly united one with the other, That it is almost Impossible to [Page 88]dis-unite them: Nevertheless, we see therein the same Effects as we know are produced in other Bodies by Acid and Al­kali, and therefore, we have good ground to believe, That these principles are also to be met with therein, and, That the same effects are produced by the same Causes. Thus, when we see Spirit of Niter and the volatile spirit of sal Armo­niack dissolve filings of Cop­per, we conclude, That there is Acid and Alkali in those fi­lings, and, That the Acid spi­rit of Niter acts on the Alkali which it finds therein; and the sharp spirit of sal Armoniack on its Acid: for, 'tis a sure Maxim That Acid spirits never act nor ferment but with Alkali's: and [Page 89]Alkali's, on the contrary, never act upon any other Bodies but Acids: and thus Mr. Boyle's Objection is of no force, seeing Spirit of Niter and Spirit of sal Armoniack meet in the filings of Copper with different Parts upon which they act different­ly, and they act not any other­wise on the same subject.

He continues his Ob­jections by an Experiment like the former: He saies, That in the Solution which is made of Iron by Acid Spirits, they are wont to attribute this Effect to the Acidity, of the Liquor which dissolved it, although Iron is dissolv'd redily enough, and also in the Cold too, in sharp Spirits.

This Objection is as easily resolved as the former: [Page 90]for there is found in Iron, as there is in Copper, Acid and Alkali; The Spirit of Niter acts on its Alkali, and the Spirit of sal Armoniack on its Sulphur or Acid, and 'tis sufficient that the one or other of these Two Liquors act upon the Alka­li or Acid of the Iron to make the Metal change its Form: as for the rest, it is sufficiently easy to know, That there are Acid and Alkali in Iron by this, That Iron cast into Cream hinders that the Butter cannot be made, in as much as it char­ges it self with the Acid which ought to make the Coagulati­on: and there are none but Al­kalies which have the Privi­ledge to produce this Effect: Acids assisting to make this Co­agulation, [Page 91]as Country-women observe; Therefore consequent­ly there may be Alkali in Iron. We see likewise by another fa­miliar Experiment, That there is Acid in Iron, for, if one puts a bit of iron into Sauce, where­in there is some Gall, as in that of a Carp, the Gall of which one has broke; all the Volatile Alkali which causes the bitter­ness of the Gall joins it self to the Iron and the Sauce re­mains sweet: How should this be, that this Volatile Alkali doth join it self to the Iron, if there was not Acid in the Iron, seeing Alkali cannot produce such an Effect; it follows there­fore, That there is Acid in Iron.

He afterwards de­mands [Page 92]the Reason, Why Mer­cury, (which dissolves Gold so readily, it being a hard and so­lid Body, and reduces it into an Amalgama) acts not at all upon filings of Iron, though this is a Metal so open that Liquors weak enough work upon it.

Two things contribute to this Effect: The first is, That there is a great deal more Sulphur in Gold than in Iron, and consequently, Mercury (which abounds in Alkali) can rather work on Gold than on Iron: The second is, That the Sulphur of Iron is intangled in a great quantity of Earth which hinders the Action of the Mer­cury which has not parts suffi­ciently subtile nor sufficiently [Page 93]penetrating to dis-intantangle it, as the Spirits of Niter and sal Armoniack do, whose parts are so thin and so agitated that they dis-intangle the parts of the Iron one from the other, and makes a Dis-union of its Sulphur and Alkali: it is not so of Gold, whose Sulphur is only intangled in its Mercury, and, which hath only a very little Earth, which is not strong enough to intangle the parts of the Sulphur and Mercury of Gold.

The same thing hap­pens, which he pursues to the same End: In the Precipitati­on which is made of Corals and Peals dissolved in distilled Vin­egar with Oil of Tartar made per deliquium: Chymists attri­bute [Page 94]this Precipitation to the Alkali of Tartar, which absorbs the Acid spirits of the Dissol­vant, and nevertheless we see That Acids precipitate them as well as Alkali's.

I do not wonder, That Acids precipitate equally with Alkali's, Corals and Pearls dis­solved in distilled Vinegar: Yet that does not at all destroy the Reason, That they are wont to render when it is made with Alkali's: for, there are, as you know, Two sorts of Dissolutions in Nature, either an Acid dis­solves an Alkali, or else an Al­kali dissolves an Acid: if it is an Alkali which holds an Acid in Dissolution, the Precipitati­on cannot be made but by an Acid, for then the Alkali which [Page 95]held it in Dissolution quits it to join it self to the new Acid that is cast thereto: If, on the contrary, 'tis an Acid which holds an Alkali in Dissolution, either the Alkali dissolved by this Acid is mixed intimately with its dissolvant, in such manner that the dissolvant fills exactly all the pores of the dissolved body, as it happens in Vitriol of Mars; or, the dissolvant do's not penetrate the Body but superficially, and do's not throughly fill the pores thereof, as we observe in Mercury dissolv'd in Aqua fort. and in Coral and Pearls dissol­ved in distilled Vinegar: If it happens that the Acid spirit penetrates intimately the Bo­to which it is joined, and that [Page 96]those points be of the same fi­gure and grossness, as the Pores of that Body, the Precipitation cannot be made but by an Alka­li which charges it self with the Acid which held that Body in dissolution, and makes it at that instant to quit its hold: The which Acids cannot do, because that not finding therein any Vacuity they cannot work up­on it. If the Dissolvant is not mingled per minima with the dissolved Bodys, an their points are not of a figure proportiona­ted to those of the pores of the Body, the Precipitation there­of may be made by Acids and Alkali's: by Alkali's after the same manner as I told you but now: and, by Acids because the points of these Acids work [Page 97]upon those of the Dissolvant, causing them to quit their hold: for, the Body being no longer agitated nor detained by those points, it falls by its own weight to the bottom of the Vessel which contains it. Thus when Oil of Tartar precipitates Corals and Pearls dissolved in distilled Vinegar, they have Reason to say, that this Preci­pitation is done, Because the Alkali of Tartar has blunted and charged it self with the points of the distilled Vinegar which held the Coral and Pearls in Dissolution, altho Acids pre­cipitate also this Dissolution.

Our Author saith, Chapter the Third, That the Admirers of Acid and Alkali seem to have assign'd, arbitrari­ly [Page 98]certain Extents and Employ­ments to each of these Princi­ples: as for Example, That an Acid doth, in quality of an A­cid, such and such Operations, and the Alkali's in their quality the like also: and, That from thence depends all the Phaeno­mena's of Nature; and, That they ought not to promote, in publishing, Propositions of this Importance, without good and sufficient Proofs thereof.

Does not Experience teach us, That Acids, of what­soev [...]r Nature they be, coagu­late Blood, Milk, &c. That they ferment with all Alkali's, and never with other Acids: That they constitute the Essence of all Bodies▪ that they are the pointed Bodies which fills up [Page 99]the Vacuities of Alkali's, and which are the absolute Masters thereof; That Alkali's, on the contrary, dissolve Blood and Milk coagulated by Acids: That they hinder them also from being coagulated; and, that their parts are not dis-united one from the other: For Ex­ample sake, If one mingle som volatile Spirit of Sal Armoni­ack with new Milk, or with Blood so soon as it comes out of the Vein, it conserves them in their Consistence for a great while, and hinders them from being corrupted: Alka­li's whiten Linnen and Stuffs; they ferment well all Acids and never with other Alkali's: These are the little Bodies full of holes and wholly vacuous: [Page 100]in a word, They precipitate Vi­triol of Mars dissolv'd in Wa­ter, which Salts nor Acids can never precipitate: You thus see plainly, That they assign not in vain, these nor several other Effects to Acid's and Al­kali's, seeing Experience teach­eth you, That they are alwaies and at all times the Cause there­of.

He affirms also, That the Division of Salts into Acid and Alkali is purely arbitrary, and, That they may divide them otherwise: Acids and Alkali's having not only in a great many things some agree­ment: but also salts of one and the same Denomination being visibly different in several chief points: as Alkali's, whereof [Page 101]some are fixed, others volatile; and some thereof give a Preci­pitation of corrosive Sublimate dissolved in water of a tawny colour, as salt of Tartar; others a white colour, as spirit of U­rine, Harts-horn, &c. Finally, some act very slowly on filings of Copper, as Oil of Tartar made per deliquium, and others dissolve it with readiness, as spirit of Urine, &c. he adds also, That there is no less Diffe­rence between Acids: some dis­solve Bodies which others can­not dissolve, as Aqua Fortis which dissolves Silver, Mercu­ry, &c. and touches not Gold: and, as Aqua Regis which dis­solves Gold, and touches nei­ther Silver nor the other Me­tals: Spirit of Vinegar well de­flegm'd [Page 102]dissolves Lead in the Cold, and reduces it into mi­nute parts, which Spirit of common Salt cannot do: and he concludes this Chap demanding whether Acid and Alkali have the Simplicity that a Philoso­pher requires in Principles? and in Smiling at the Definition that they are Wont to give, That Acid is an Enemy to Al­kali, and Alkali to Acid.

The Division of simple Salts into Acid and Alkali is as Just and Exact as can be wish'd; Acids and Alkali's having not any agreement in Virtue and Property, and the one never produceth the Effects of the other: as Mr. Boyle would have it: as for Example, Alka­li's are Bodies vacuous and full [Page 103]of holes, which precipitate Vi­triol of Mars dissolved in Wa­ter, which whiten Linnen and Stuffs; which make a Dissolu­tion of Milk and Blood coagala­ted by Acids. &c. Acids, on the contrary, are pointed Bodys, which fill up the little holes they meet with in Alkali's, which foul Linnen and Stuffs, which coagulate Blood and Milk, &c. in a word, which have not any of the Properties of Alkali's. And, though Salts of one and the same Denomina­tion differ in some things, yet nevertheless, they all agree in Nature and use: for we see. That Alkali's, whether fixed or volatile, are Bodys full of holes, That they all precipitate Vitri­ol of Mars: That Acids, on [Page 104]the contrary, are pointed Bo­dies, &c. so that when some Alkali's precipitate corrosive Sublimate dissolved in water, into a tawny coloured Powder, and some others into a white powder, that does not prove, That they have a different Na­ture one from the other, but that comes from the Diversity of their Pores, some having them more conformable to the Acid which had sublimed the Mercury and others less, and they blunt after this manner more or less the points of those Acids, whence comes the Di­versity of colours of the pre­cipitate: It is not also the Diversity of Natures that makes that Volatile Alkali's dissolves Copper more rea­dily [Page 105]than fixed Alkali's do: but only the greater agitation of their parts: all Acids work on Silver and the other Metals, but more or less, according to the greater or lesser Relation their points have with the pores of those Metals: These Acids never work on Gold which cannot be dissolved but by salt Menstruums, as I have said else-where. And, whatso­ever Mr. Boyle says of spirit of Salt, which he cites for a most powerful Acid, is Salt, and not a pure Acid, notwithstanding the Acid seems to predominate therein: and, That is the Reason why spirit of Salt works neither on silver nor the other Metals.

These two Salts have the [Page 106]Simplicity that a Philosopher requires in Principles, because they are composed of Particles of one and the same Nature, and can never be resolv'd into any other Substances. In respect of the Definition which Mr. Boyle relates of Acid and Alkali, he has Reason to blame it, be­cause he doth in no wise ex­plain the Nature of these Prin­ciples, no more than if one should say, That that which dissolves a Body dissolvable by an Acid, ought to be an Acid: &, That all which precipitates a body dissolv'd by an Acid, ought to be an Alkali: but Mr. Boyle cannot say the same thing of the Definition which I have al­ready so many times repeated concerning Acid and, Alkali: [Page 107]That the Acid is a Salt com­posed of small pointed parts which ferment with Alkali's & makes the Essence of all Bo­dies: The Alkali, on the con­trary, is a vacuous Salt which ferments with Acids, and pre­cipitates Vitriol of Mars dissol­ved in water. This Definiti­on explains clearly their Na­ture, Kind and Difference; for, these two Principles agree in that they are Salts; and they differ in that one of them is pointed, and the other porous and unequal, and that one fills the Pores of the other, and is its absolute Master.

This Famous English-Man will not allow, Chap. 4. That the Fermentation or Heat and Ebu­lition which is caused when [Page 108]these Two Salts are mingled to­gether, is a sure Token to know Acid and Alkali: For, he pre­tends, That these Effects depend principally on the Mechanick Disposition and Construction of Parts; and, That 'tis suffici­ent to produce heat when the parts of a Body are agitated with vehemence on all sides: and, for the Ebulition, That the Bo­dies which are mingled inter­cept the parts of the air, or the warm Vapours in the time that they are excited; and, That there happens often in this mi­xture Heat without Ebulition, and Ebulition without Heat: He relates some Experiments of both: For, he saith, When Oil of Vitriol, which is a pow­erful Acid; or, Salt of Tartar, [Page 109]which is a powerful Alkali, are mingled with Water which is neither Acid nor Alkali; There is at that time a considerable heat excited, without any Ebu­lition: and, That on the con­trary, in the Mixture which is made of spirit of verdigriss, made per se, which is an Acid, with salt of Tartar: there is made a great Ebulition and gross Froth without any re­markable heat.

It is very true, That the Heat and Ebulition which happens in Fermentation de­pends upon the Mechanick dis­position and Construction of the parts of Bodys which are Fer­mented: But this Construction or Disposition likewise depends wholly upon the different na­ture [Page 110]of Acids and Alkali's, and their divers mixtures one with the other, as I have already caused you to observe, where I spoke of Fermentation and its Differences, which would be needless here to repeat: as for the oil of Vitriol and Salt of Tartar which heat water when they are dissolved therein; you shall observe, That there is in Oil of vitriol, a metallick part of Iron or Copper according to the Nature of the Vitriol which was elevated in the Distillati­on by the Acid of that Salt, as Experience sufficiently teach­eth us: This oil coming to be dissolved in the water, there is then made a separation of the Metallick part from the Acid, which had elevated it; and an [Page 111]action of that Acid upon the Al­kali of the water; which is powerful enough, since it har­dens red hot Iron, and hinders it from going into scoria's, when it is squenched therein, for, there is none but Alkali's which can produce this effect: then there is made on all sides an agitation of their parts, with sufficient Vehemence, whence comes the heat which happens in this mixture. In regard of that which results from the mi­xture of salt of Tartar with wa­ter, you shall understand that salt of Tartar does hot heat wa­ter, but when it is too much or too little calcined: when it is too much calcined, it is char­ged with an Acid from the fire, which coming to be dissolved [Page 112]in water, it separates it self from the Alkali of the Tartar, and acts upon that of the water, and causes, as I have said but now, the heat in the water: and when the Tartar is not suffici­ently calcined, it retains some of its own Acid, and becomes a little near the nature of Calx vive, which causes it to fer­ment in water: but when this Salt is neither too much nor too little calcined, it dissolves sim­ply in water without causing therein any Heat, as all pure Alkali's do.

He afterwards comes to speak of the Tast, which he saies, is as the Touch-stone to know Acids and Alkali's: he saith thereupon, That there are a great many mixts, in which [Page 113]the Tast can so little discern which of those two Principles predominate therein, that one cannot suspect that there is in those two Bodys the least part of those Two Salts, as in Dia­mons, Rubys, Gold, Silver, &c. That there are also several Bo­dys which abound in Acid and Alkali Salts, yet have no tast at all, or, which have one altogether different from that which the Chymists attribute to their Principles, as Venice Glass, which is insipid on the Tongue, though it is almost no other thing but fixt Alkali; and as Cristals of Silver and Lead made with aqua fortis, where­of the first has an extream Bit­terness, and the last, the sweet­ness of Sugar; neither of which [Page 114]retain any thing of Acid of the aq. Fort. which did dissolve those Metals.

By the Taste we can only know pure Acids and Al­kalis, as the Spirits of Sulphur, Niter, &c. which are taken Notice of by their acidity: and as the volatile Alkali's of Vi­per, Harts-horn, and fixed Al­kali's as lixivial. Salts, which are known by their great a­crimony: as soon as these two Salts are mixt together they produce different Savours ac­cording to the divers Mixture and particular figure of their Parts: It happens also very of­ten that a body which experi­ence teacheth us a acid, be­ing mingled with a Body which experience makes us know [Page 115]to be an Alkali, they being in­sipid: as for Example, When four parts of Cream of Tartar dissolved in Water: in which may be manifestly seen, that the Acid predominates, is mingled with two parts of Salt of Tartar dissolved also in water, there is made as soon as they come together a Fermentation sufficiently violent, from which afterwards is obtained, by Cri­stallization, a salt which is al­together insipid. You see by this Experiment, That though a Bo­dy be insipid, nevertheless one may not conclude, That it c [...]n­tains neither Acid nor Alk [...]li [...] therein.

Mr. Boyle pretends is the fifth Chapter, That the Hy­pothesis of Acid and Alkali is [Page 116]neither Necessary nor Useful to explain that which happens to qualitys; Whereof some are produced, others destroy'd or altered; it not appearing, Th [...]t these two Principles contribu­ted in any wise thereto; as when Water is changed by the force of Beating into Froth, which hath some Consistence: or, as when Coral which is red and transparent, is changed in­to a white and opacous Pow­der, without doing any other thing thereto than reducing it into a Powder sufficiently sub­til to pass through a fine Searce.

The Froth which is formed on water by Beating comes only from the agitation of its parts, and as there are a [Page 117]great many Alkali parts, and also some Acid parts, and a lit­tle Earth to be met with in wa­ter, it is certain, That these Principles contribute to the Production of this Quality. It should be needful that Mr Boyle prove, That there is no Acid nor Alkali in water, to conclude That Acid and Alkali do not contribute in any wise to the production of this new Quality; which is impossible to be done: as for the Coral, which be­comes white and opacous when it is reduced into an Impalpa­ble Powder: I shall tell you, That the most part of Bodies are destroy'd by Trituration, and entirely change their Nature, and those also which are harder and solider: and if we may be­lieve [Page 118]some, of the Renouned Chymists of our Age, as the famous Langelot, Olaus; Bor­rychius, Schroder, &c. Leaf-Gold is destroyed in such wise by a long Trituration, that it is impossible to make it retake the form of Gold, whatsoever artifice you use: so that it is not strange, That Coral which is red and transparent, should become white and opacous, when it is reduced to an impal­pable powder, because that in the Trituration which is made thereof, its parts are dis-united in such wise one from the other, and are in so great a confusion, that they can no longer keep their natural colour, either be­cause they do no longer reflect the light as they did reflect it [Page 119]before; or, because they do not make the same. Impression on the aier: or lastly, that the, Attoms which go out there­from are not conditioned as they were: and this colour cannot return to it, except by the force of some exteriour a­gent its particles retake the same place, and the same sci­tuation as they occupied before the Trituration: as we take notice of it in blew Vitriol, which becomes white when re­duced into pouder, and which retakes its natural colour when this powder is dissolved in wa­ter, and afterwards caused to cristallize.

He proceeds with an Objection like the former; He saies, They cannot render a [Page 120]Reason by Acid and Alkali of Gravity, Light, and several o­ther Qualities, which are called MANIFEST; and much less of those which are called OC­CULT: as of the Force of the Loadstone on Iron, and of Iron on the Loadstone, as well as se­veral other Phaenomena's of the Loadstone.

The gravity and levi­ty of a body depends upon the more or less of Vacuity that there is in that body, according to Mr. Boyle's Opinion, in such manner, That a body in which there are fewest Vacuities, is most Weight, as, on the con­trary, that in which there are more vacuitys, is more light. Now the Moreness or Lessness of Vacuities depends upon the [Page 121]Moreness or Lessness of the acid which there is in Bodies: for, when there is a great deal of Acid therein, the Pores of the Alkali are filled therewith; and, when on the contrary, there is but a very little Acid, those Pores remain empty, and consequently the gravity of a Body depends upon the quanti­ty of Acid that is found therein, and the Levity upon the small­ness of the Acid and quantity of Alkali which is found there­in: The abundance of Caput Mort. contributes much to the lightness of Bodys, as we observe in the Firr-tree which is a ve­ry light wood, and hath much Earth in it. Light is no other but an agitation of small poin­ted Bodys which are poured [Page 122]out in the air, and puts all the parts thereof in Motion: It is of the same Nature with fire since it produceth the same Ef­fects, and that being re-united in a burning-glass, it liquefies Metals and calcines Stones as fire doth, which is Acid, as I have proved else-where, and by consequence Light ought also to be an Acid, since it hath all the qualities thereof. The Ef­fects which are attributed to qualities, and are called. OC­CULT draw no less their Ori­ginal from Acid, and Alkali than the manifest Qualities, which I shall shew you when I speak of some Effects of the Load-stone; The most consi­derable whereof is, That where­by it draweth Iron. You shall [Page 123]take notice therefore, That I­ron is an imperfect Load stone, which hath Pores of the same figure with those of the Load-stone, and which are filled with the same Particles as those wherewith the Load-stone is fil­led. We see likewise, That I­ron, exposed to the air a long time, becomes Load-stone, since it acquires the qualitys thereof, as the Crosses which are upon Churches, these in Succession of time become Load-stones, and produce the same Effect as the Load-stone. You shall like­wise take notice, That there are a great many more Pores in the Load-stone than there is in Iron, and, That the force of the Load-stone consists in the small pointed Bodyes that fill [Page 124]these pores; Iron becoming Load-stone in the air, furnisheth us with a most convincing Proof thereof; for, Experience teach­eth us, That all porous Bodies are charged in the air, with an Acid of their own nature, as the earth from whence Salt-petar has been drawn, which is there­in charged with a new Salt-pe­tar, which is acid, &c. Lastly, you shall observe, That there goes out continually from the Loadstone a multitude of these little pointed bodies, and at the same time there enters therein­to others which retake their place, because the air is wholly filled therewith: This being granted, it is sufficiently easy to render a reason for the attracti­on of Iron by the Load-stone. [Page 125]The attoms which go out con­tinually from the Load-stone insinuate themselves into the Pores of the Iron and fills them, These Corpuscles cannot go out from the Load-stone, but at the same time they agitate the air with violence, this agitated air throws the Iron against the Load-stone, or the Load-stone against the Iron, according as the one of these Bodies resists it, and after this manner the Load-stone attracts Iron, and Iron the Load-stone. You see plainly, That this Virtue, which did for­merly silence all the Philoso­phers, is explained by our Hy­pothesis, and that, after a man­ner so natural, that it is easy to judge, That all the other Phe­nomena's of the Load-stone [Page 126]ought as certainly to be produ­ced according to our Princi­ples.

Mr. Boyle, in Conclu­sion, Makes an Objection, which to me seems sufficiently strong: he demands, How in the Disso­lution of Metals, their Parts are sustained by the Dissolvant, though the Mettal be in equal bulk nine times heavier than the water; and if it be Gold, nine times heavier than the liquor which hinders it from sinking, and always a great deal heavier in particular, than the Salts which compose the Dissolvant, can render the water in which they are mingled.

It is easy to compre­hend how the parts of Metals dissolved in Acid spirits, sharp [Page 127]Spirits and salt Mestruums are sustained by these Dissovants: It is because their parts are con­tinually agitated by those of those Liquors whose motion is sufficiently strong, an sufficient­ly rapid to carry them with them, and to hinder them from precipitating.

I did not believe, That you were able, without seeking some other Principles than these which you have established, to satisfy the Objections of the il­lustrious Mr. Boyle: But you raised all the Difficulties there­of with so much Force, that they have only served to give a greater illustration to your Prin­ciples, and to shew the extent thereof, and their Conformity, to Reason and Experience.

[Page 128]

NOW, seeing a Genius so delicate, and which knows Na­ture so exactly, as that Learned Man, has not been able to give them any Attaint, I doubt not but day by day they will be confirmed, as we make new Discoveries therein; and, that they will remain firm and stead­fast against all that can be em­ploy'd to shake and destroy them.