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A L K

ALL

tipathy to Acids, will readily diffolve crude Iron even in the Cold. . ,. .,

Further, the Patrons of this Hypotheiis, feem arbitrarily to have affigned Offices to each of their two Principles.as the Chymifts do to each of their trie, prima ; and the Peripa- teticks to each of their four Elements.— But tis not enough to fay, that an Acid, for inftance, performs theie things, and an Alkaly thofe ; and that they div.de the Ope- Phainoinena of natural Bodies between them ■

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dity in the Mouth ; the latter having a faccharine Sweet- nefs, and the former an extreme Bitternefs. And even in Vegetable Subftances of a manifeft Tafte, 'tis not eafy to know by that, whether it be the Acid or the Alkaline Principle which predominates in 'em : As, in the effential Oils of Spices, and the grot's empyreumatical Oils of Wood - and even in Alcohol of Wine, which fome contend to be an Acid,andothers,an^fai/r. ImperfeS.ofCbym. DcR.oft%u a i ALKALIZATE, or Alkaline Bodies, among (Jhy-

fether Proof, indeed, the fery Distribution of Sahs into the, , are & , to . b

Acids and Alkalies, has fomewhat arbitrary in it ; there be- ing not only feveral things wherein the Acids agree with Jkalies, bur alfo feveral things wherein each differs rom it felfi— To fay nothing of the Diverfity of fix d and volatile Alkates ahovemention'd ; fome, as Salt of Tartar, will precipitate the Solution of Sublimate into an Orange-taw- ny • others, as Spirit of Blood and Hartftiorn, precipitate fuch a Solution into a milky Subftance ; and Oil of Tartar very (lowly operates upon Filings of Copper, which Spi- rits of Urine and Hartihorn will readily diffolve in the Fire. And among Acids themfelves the difference is no lefs ; tor fome of them will diffolve Bodies that others will not : and this even where the Menftruum that will not diffolve the Body, is reputed much fironger than that which does ; as dephlegmated Spirit of Vinegar will diffolve Lead reduced to minute Parts in the cold, which is an Effect that Chy- inifls expect not from Spirit of Salt. Nay, one Acid will precipitate what another has diffolved, and i contra ; as, Spi- rit of Salt will precipitate Silver out of Spirit of Nitre. Add, the Properties peculiar to fome particular Acids, as that Spirit of Nitre or Aqua fortis, diffolves Camphire into an Oil, and coagulates common Oil into a confident Subllance like Tallow ; and tho it will both corrode Silver, Copper, Lead, and Mercury, and keep them diffolved, it quickly lets fall almoft the whole Body of Tin.

'Tis no wonder that the Definitions given of Acid and Alkaly (hould be inaccurate and fuperficial ; fince the Chy- mifts themfelves do not feem to have any determinate No- tion of furc Marks, whereby to know them diiiinftly.— For, to infer, that, becaufc a Body diffolves another, which is diffoluble by this or that known Acid, the Solvent mull alb be Acid ; or to conclude, that, if a Body precipitates a dii- folved Metal out of a confeffcdly acid Menftruum, the ire- cipitant nil be an Alkaly, is precarious : fince Filings of Spelter will be diffolved by fome Alkalies, viz. Spirit of Sal Ammoniack.^c. as well as bv Acids; and Bodies may be pre- cipitated out of acid Menttrua, by other Acids, and by Li- quors wherein there appears not the lead Alkaly. Add, that a Solution of Tin-glafs, made in Aqua fortis, would he precipitated both by Spirit of Salt, and by con ™ on Water. — Nor does that other Criterion of Acids and Alka- lies, viz. the Heat, Commotion, and Bubbles excited upon their being put together, appear more determinate; fince almoft any thing fitted varioufly and vehemently to agitate the minute Parts of a Body, will produce heat in it.— Thus, tho Water be neither an Acid nor an Alkaly, it will quick- ly grow very hot, not only with the highly acid Oil ofVi- trio", but with the alkalizate Salt of Tartar. See Heat.

Neither is the Production of Bubbles, tho accompany'd with a hiffing Noife, a certain Sign ; fuch Produftion not being a neceffary Effect of Heat, excited by Con- flict, but depending on the peculiar Difpofition of the Bo- dies' put together, to extricate, produce, or intercept Parti- cles of Air.— Hence, as Oil of Vitriol, mix'd in a due Pro- portion with fair Water, may be brought to make the Wa- ter very hot, without exciting Bubbles : fo Mr. "Boyle has found, that alkalizate Spirit of Urine, drawn with fome kinds of Quick-lime, being mixed with Oil of Vitriol moderately flrong, would afford an intenfe heat, whillt it produced either no manifeft Bubbles at all, or fcarce any ; tho the urinous Spirit was ftrong, and in other Trials operated like an Alkaly : and tho with the Spirit of Urine made per fe, in the common way, Oil of Vitriol will pro- duce a great hiffing, and a multitude of confpicuous Bubbles. On the other fide, fome acid Spirirs, as of Verdegreafe, made pure, poured on Salt of Tarrar, will frequently make a Conflict, and produce a large froth ; tho not accompany'd with any manifeft heat. Sec Ebullition.

Many make the Tafte the Touchftone whereby to try Acids and Alkalies : But there is a multitude of Bodies, wherein we can fo little dilcern by the Tafte which of the Principles is predominant, that one would not fufpect there was a Grain of either of them therein : Such are Dia- monds, moll Gems, and many ignobler Stones ; Gold, Sil- ver, Mercury, ££*c There are alfo Bodies abounding with acid or alkalizate Salts ; which either have no Tafte, or a quite different one from that of the chymical Principles.— Thus, tho Venice-glafs be in great part compofed of a fix'd Alkaly, it is infipid on the Palate : And Cryflals of Silver and Lead, made with Aqua fortis, and containing numerous acid Particles of the Menftruum, manifeft nothing of Aci-

pierced, and put into Motion by the Points of an Acid poured upon them. See Alkaly.

ALKEKENGI, a Medicinal Fruit, produced by a Plant of the fame Denomination, and popularly called Winter- Cherry.

The Plant bears a near refemblance to Solanum or Kight. fhade ; whence it is frequently called in Latin by that

Name, with the Addition or Epithet of Veficarinm It ; s

fometimes alfo called Halicacabum.

The Fruit is celebrated for its lithontriptic Quality; and prefcribed to cleanfe the Urinary Paffages of Gravel, and other Obftruclions. Its deterfive Quality alfo recommends it againft the Jaundice, and other Diforders of the Vifcera.

The Trocbifibi Alkekengi, prepared from it, are but lit- tle prefcrib'd in the modern Practice. See Troche.

ALKERMES, in Medicine, iSc. a Term borrow'd from the Arabs.— The Confection of Alkermes, is a celebrated Remedy, of the Form and Confidence of a Confection ; whereof the Kermes Berries are the Bafis. See Confec- tion, and Kermes.

The other Ingredients, as prefcribed by the College, are Pippin-Cyder, Rofe-Water, Sugar, Ambergreafe, Mufk, Cinnamon, Aloes Wood, Pearls, and Leaf Gold. — But the Sweets ate ufually omitted.

It is much ufed as a Cordial ; efpecially, fays Dr. §>uiMy, among Female Prefcribers, and in complaifance to them : But that Author decries its Value in that Intention, and thinks it ought only to be regarded as a Sweetner.

ALLANTOIS, Allanyoipes, in Anatomy, a third Coat or Membrane of a Fcetus, invefling part thereof, in manner of a Scarf, or Collar, extending from the Cartilega Xiphoides, to the bottom of the Hips. See Foetus.

The Allantois makes part of the Secundine. — It is con- ceived as an urinary Tunic, placed between the Amnion and Chorion, which by the Navel and Urachus receives the U- rine that comes out of the Bladder. See Secundine, and Urine.

'Tis a Point controverted among Anatomifls, whether the Allantois be found in Man. — M. (Drelincourt, Profeffor of Anatomy at Leiden, in an exprefs Differtation on this Mem- brane, maintains ir peculiar to the Ruminating Kind. See Ruminant.

Dr. Hale, on the contrary, has given an accurate Defcrip- tion of the human Allantois ; and affign'd the Reafon why thofe who believed its Exiftence had not before fully found it out ; and alfo an anfwer ro thofe who yet deny its reality. See "Pbiloftpb. Tranfetl. N° 271.

The Word is derived from aAAaV, Farcimen, a Gut, and lijln, Forma, Shape ; becaufe, in many Brutes, it is in the Shape of a Gut- pudding : but in Man, and fome others, it is round. — It is likewife called Farciminalis.

ALLEGATION, the Citation, or Quotation of an Au- thority, Book.Paffage, £?c to make good any Point.or Affer- tion. See Quotation, Citation, Authority, £S?c.

ALLEGIANCE, the legal Faith and Obedience, which every Subject bears to his Prince. See King, Fealty, £J?c.

This was antiently called Ligence ; from the Latin Li- care, and Alligare, to bind, q.d. Ligamenfidei. See Liege.

Oalb of Allegiance, is an Oath given in England to the King, in quality of a Temporal Prince or Sovereign ; to diflinguifh it from the Oath given to him as Primate, or fupreme Head of the Church, which is called the Oath of Supremacy. See Oath ; fee alfo King, and Supremacy.

In this Senfe, the Word Allegiance comes from the Latin ad Legem. — The Quakers arc difpenfed with not taking the Oath of Allegiance ; and in lieu thereof are only enjoin'd a Declaration. See Declaration.

ALLEGORY, Allegoria, a Figute in Rhetorick, whereby we make ufe of Terms which in their proper Sig- nification, mean fomething elfe than what they are here in- tended to denote : Or, it is a Figure, whereby we fay one thing, expecting it ihall be undcrllood of another, to which it alludes. See Figure, Allusion, ££c.

An Allegory is properly a Series, or Cominuation of Me- taphors. See Metaphor.

Such is that beautiful Allegory in Horace, Lib. J. Od. 14.

Navis, referent in mare te novi FluBus, &c. Where the Ship, Hands for the Republick ; Waves, for Civil War; "Port for Trace and Concord; Oars for Soldi- ers ; Mariners for Magiftrates, ckc.