poffible to do it at all; Tryals of the Operations of these Salts upon one another have taught Inquirers, that there are likewife among those Laws obferved by the Acid and Alcaline Salts, fome whereby this ftri&t and clofe Union may be very eafily, and yet as it were miraculously diffolved, and each of them separated from the other in fuch a manner, as if one of them thruft t'other Way, or at leaft quitted its hold, without any external Cause that we have as yet been able to discover.

Thus we find, that one Acid feems ftronger than another, and that how strictly foever fome Acids are joined with Alcalies, one need do no more in many Cafes than to put another Acid to it, whereby to oblige the firft Acid to forfake its Alcali, and then the fecond will unite itfself to it. The fame thing does likewife obtain in Alcalies, so that one of them fhall immediately feparate itfelf from its Acid, and leave the latter to be join'd thereto.

Many Inftances thereof may be met with in Chymistry, but we fhall content ourselves with quoting one of each.

Pour Spirit of Sea-Salt, which is an Acid, upon the Alcaline Salt of Tartar, they will effervefce, and unite themselves into a third mix'd Salt, which is like the Sea Salt: But how much Fire and Pains it will coft to feparate this Acid Spirit of Salt from the Alcaline Salt of Tartar, is well known to those that have made the Tryal; but if you put a little Water to it, and fome of the Acid Spirit of Salt-Petre, the Acid of the Sea-Salt will quit its Alcali without any Trouble, and fuffer itfelf to be drawn off by a fmall Fire; whilft at the fame time the faid Spirit of Salt-Petre unites itself with the Alcali, or Salt of Tartar, and thereupon produces a new matter of Burning Salt-Petre, upon which if you pour again an Acid Spirit of Cop

peras

peras with a little Water, there will be another Separation between the Acid Spirit of Salt-Petre and the faid Alcali; which may likewise be extracted from thence with a foft Fire from Sand; and this third Acid,or Spirit of Vitriol, will unite itself to the Salt of Tartar, from which there will refult another Salt, almost of the fame kind with that which is commonly called Tartarus Vitriolatus. To fhew the fame likewife in the Operation of feveral Alcalies, pour the faid Spirit of Sea-Salt upon the Volatile Alcaline Salt of Animals, of Hartshorn, of Sal Armoniac, and the like, diffolved in Water, whereupon, after an Effervefcence, they are united into a third, like Sal Armoniac, and the Volatile Salt will thereupon lose a great part of its Volatility and Scent in the Mixture. Now if you add Salt of Tartar for a fecond Alcali, it will feparate the firft, and difcover itself prefently by a new ftrong Smell, and the fecond Alcali, or Salt of Tartar, will unite itself with the Acid of Sea-Salt. They that have a mind to fee feveral Kinds of Alcalies, the firft of which, by the Addition of a fecond, will feparate itself from the Acid, may be pleased to confult the following Contemplation, Sect. VI. besides innumerable Inftances wherewith Chymistry can furnifh 'em ; but we fhall not, nor cannot here determine any thing about the Manner ufed herein by the wonderful Power of God, reckoning it fufficient that the thing is plain enough in itself.

SECT. V. Acid Salts difperfed in many Bodies.

Ir must not be thought, that thefe Effervefcences, and Actions of Acids and Alcalies, have only place in Chymical Liquors, and that we therefore go too far in honouring them with the great Name of a Law of Nature; forafmuch as they,

that

that is, one or other of them, are found in many Terreftrial Bodies, and that a great deal of that Matter of which many Bodies are compofed, may be reduced to Acids or Alcalies.

To fhew this in the Acid:

In Animals all the Milk and Serum, or Whey, is Acid; not to enumerate any other Juices here, particularly those Acid Humours which oftentimes occur in many unhealthy Creatures; or, as fome maintain, are always found in the Stomach of healthy ones.

We likewife meet with Acids in Minerals, as in Sulphur, Copperas, Allum, Salt-Petre, Sea and Rock-Salt, in Antimony and others.

In Plants we likewife find some that yield an Acid Spirit by Diftillation; befides all those Fruits which are foure because they are not ripe, we meet with an infinite number, which after they are come to their full Ripenefs, do retain an entire Acid or fourifh Tafte; fuch as Currants, Oranges and Limons, many Apples and Pears, and the like. Befides that almost all Liquors proceeding from Plants, or other things, by way of Fermentation, fuch as Beers, Wines, and the like, will turn to an Acid or Vinegar.

The Air itself feems to be impregnated with foure Particles, fince it will corrode and cause Iron to ruft.

There are likewife Medicinal Springs that yield fourish Waters, found in many Countries; fee Varenius's Geography, Part. abs Cap. 17. Sect. 6. of which he makes the number in Germany alone to amount to about 1000; fo that from hence may be inferred the Quantity of Acids difperfed throughout the whole Earth.

SECT.