in Motion, cools more than it heats; as appears from Winds, Bellows, &c. For this Motion is not fo rapid as to excite Heat; and is a Motion of the Whole, not of the Particles: whence 'tis no wonder it should not generate Heat.

A twenty-third; to the feventeenth.

(23.) This Instance should be diligently enquired into; for all Herbs heatHerbs, and green and moist Vegetables, feem to contain fome fecret ing. Heat, tho' Jo fmall, as to be imperceptible to the Touch in Small Portions: but when many are join'd, and close fout up together, fo that their Spirit cannot breath out into the Air, but the Parts must mutually foment and cherish each other; a manifeft Heat is produced; and fometimes a Flame, if the Matter be difpofed thereto.

A twenty-fourth; to the eighteenth.

(24.) This Inftance alfo fhould be carefully examined: for Quick- Quicklime lime feems to conceive Heat, when Water is thrown upon it; either flaked, by the uniting of the Heat, which was before scattered; as in the Cafe of confined Vegetables, just now mentioned; or because the fiery Spirit is irritated, or exasperated, by the Water, fo as to make a Conflict and Struggle. This Matter might be easily determined, by ufing Oil instead of Water; becaufe Oil would ferve, as well as Water, to unite, but not to irritate, the included Spirit. The Experiment alfo fhould be extended, as well to the Afbes and the Calxes of different Bodies, as to the Ufe of different Liquors e.

A twenty-fifth; to the nineteenth.

25. This Inftance has the Negative of all other Metals; which Metals in are more foft and yielding: thus Gold diffolved in Aqua Regia, Lead Solution in Aqua Fortis, and Quickfilver in Aqua Regia, afford litile Heat to the Touch, in the Act of Solution : but Silver, and Copper, afford

found fo great, as to burn the Fingers, when taken up directly. But it is not certain, that Bullets acquire Heat, barely by moving through the Air. This might be commodioufly tried with a Wind-Gun, and a proper Inftrument for discovering a small Degree of Heat.

See above, Tab. I. §. (17.)

See Mr. Boyle's Works, paffim; and the Medicinal Use of Lime-Water, in the French Memoirs, An. 1700.

! See the History of Condensation and Rarifaction, Vol. III. Sect. VIII, p. 554,555.

Heat of Animals.

crements.

more; Tin ftill more; and Iron the most of all: and in the two latter, befides a ftrong Heat, there is alfo excited a violent Ebullition in the Diffolution. Whence the Heat feems to proceed from the Conflict; whilst the acid Spirits enter, force into, feparate, and divide the Parts of the refifting Body: but where the Body yields eafily, there is little Heat produced 8.

A twenty-fixth; to the twentieth.

(26.) To the Heat of Animals, we annex no Negative; except that of Infects, as was before obferved, on account of the Smallness of their Bodies. For Fish, compared with Land Animals, have rather a Degree of Heat, than a Privation. But in Vegetables and Plants there is no Degree of Heat perceptible to the Touch; neither in their Tears, nor in their medullary Parts, newly laid open. In Animals there is found a great Diverfity of Heat, not only in their Parts (as the Heat of the Heart differs from that of the Brain; and this again from that of the external Parts;) but also with regard to Accidents; as in violent Exercife, Fevers, &c.

A twenty-feventh; to the twenty-first.

Heat of Ex- (27) A Negative can scarce be fubjoined to this Inftance; fince even the ftale Excrements of Animals have a manifest potential Heat; as we fee in the manuring of Land.

Heat of

A twenty-eighth; to the twenty-fecond, and twenty-third. (28.) Such Liquors, whether aqueous or oleaginous, as have a Menftruums. great and powerful Acrimony, produce the Effects of Heat, in the Separation and Burning of Bodies, after fome Time; tho' at first fuch Liquors were not hot to the Touch. And thefe Liquors operate according to the Pores of the Body, whereto they are applied; for Aqua Regia diffolves Gold, and not Silver; Aqua Fortis diffolves Silver, and not Gold; but neither of them diffolves Glass: and fo of LiA twenty

quors.

The other Solutions and Mixtures, wherein Heat is generated, might also be produced as Inftances to the prefent Purpose. See the Chapter of Fire, in Boerhaave's Chemistry.

See above, Tab. I. §. (20.)

See the Chapter of Menftruums, in Boerhaave's Chemistry.

A twenty-ninth; to the twenty-fourth.

Wine.

(29.) Let Trial be made of Spirit of Wine upon Wood, Butter, Spirit of Wax, or Pitch; whether, by its Heat, it will, in fome degree, diffolve them: for the twenty-fourth Inftance fhews, that Spirit of Wine has a Power refembling that of Heat, in Scorching; and therefore, let the Experiment be made alfo in Liquefaction. Let Trial likewife be made by a Water-Thermometer, with a Hollow in the Top, on the out fide; and pour high rectified Spirit of Wine into that Hollow; then cover it, the better to keep in the Heat; and obferve whether it makes the Water fall or rife *.

A thirtieth; to the twenty-fifth.

(30.) Spices, and Plants that prove acrimonious to the Palate, Aromatics. are found much hotter when taken internally: let it therefore be confidered in what other respects they may have the Effect of Heat. 'Tis related by Sailors, that when large Parcels of Spices, which have been long kept clofe confin'd, come to be opened, those who first take them out, run the hazard of catching Fevers, and Inflammations of the Spirits. Trial, therefore, might be made whether the Powders of fuch Spices and Herbs would not, like the Smoak of a Fire, dry Bacon or Fish hung over them.

A thirty-firft; to the twenty-fixth.

(31.) There is an Acrimony or Pugency both in cold Things, Cold Things, fuch as Vinegar and Oil of Vitriol; and in thofe potentially hot, fuch as Oil of Origanum, &c. whence they both alike cause Pain in animate Bodies; and feparate and confume the Parts in fuch as are inanimate. Nor is any Negative annexed to this Inftance. there is no Pain in Animals, without a certain Senfation of Heat.

A thirty-fecond; to the twenty-seventh.

But

(32.) There are many Actions in common to Heat and Cold, tho' Some Actithey differ greatly in the Manner. Thus Snow feems to burn foon after it is handled; Cold preferves Flesh from Putrefaction, as to Heat and

ons common

Well Cold.

* See the Chapter of Fire, in Boerhaave's Chemistry.

well as the Fire; and Heat makes fome Bodies fhrink, as well as Cold. But 'tis more proper to refer thefe and the like Inftances to the Enquiry about Cold.

A third Table

APHORISM XIII.

26. In the third Place, thofe Inftances must be brought before the to be formed. Understanding, in which the Nature enquired after refides, according to the Degree of more or lefs; whether the Comparison of Increase and Decrease be made in the fame Subject, or refpectively in different Subjects for as the Form of a Thing, is the very Thing itfelf; or as a Thing differs not from the Form, otherwife than Appearance does from Existence, External from Internal, or with refpect to Man, and with refpect to the Univerfe; it foliows, that no Nature fhould be received as a true Form, unless it perpetually decrease when the Nature decreases ; and perpetually increase when the Nature increases. The Table reprefenting this, we therefore, call the TABLE OF DEGREES, or the Table of Comparison.

Heat.

The compara27. We shall first, therefore, confider fuch Things, as to the Touch tive Degrees of fhew no Degree of Heat at all; but feem only to have a certain potential Heat, or a Difpofition and Preparation towards actual Heat: and next proceed to fuch as are actually hot, or hot to the Touch; and obferve their different Strengths, or. Degrees.

hot in itself.

TABLE III.

A TABLE of the DEGREES of HEAT.

No Matter (1.) A Mong all the folid and tangible Bodies, there is nothing found originally hot, in its own Nature; no Stone, Metal, Sulphur, or other Fofil; no Wood, Water, or animal Carcass: for the Water of hot Wells feems to be heated accidentally, either by Flame, or fubteraneous Fire, fuch as is thrown up by Ætna, and many other burning Mountains; or elfe by the Conflict of Bodies; as Heat is produced

1 See Mr. Boyle's Hiftory of Cold.

m_Thefe Expreffions may give us a fuller Information, as to what the Author means by Forms.

produced in the Diffolutions of Iron or Tinn. Therefore to the human Touch, there is no degree of Heat in inanimate Bodies. And thofe we have mentioned alfo differ in degree of Heat; for Wood is not fo cold as Iron. But this belongs to the Table of Degrees, for the History of Cold.

Heats.

(2.) But for potential Heats and Difpofitions to Flame, there Potential are numerous inanimate Bodies found greatly difpofed thereto; fuch as Sulphur, Naphtha, and Petreol.

(3.) The Bodies that are previously heated, as Horfe-dung in the Animal, Quick-lime, and perhaps Afbes or Soot, by the Fire; retain fome fecret Remains of their former Heat: whence certain Digeftions, Diftillations and Separations are made of Bodies by burying them in Horfe-dung; and thus Heat is excited in Quick-lime, by throwiny Water upon it, as was above obferved °.

(4.) Among Vegetables there is no Plant, or part of a Plant, whether the excreted Tear, or internal Pitch, found hot to the human Touch: but green Plants, as above inftanced, become hot by Preffure; and fome Vegetables are found hot, others cold, to the internal Touch, viz. to the Palate or Stomach, or even to the external Parts, after continuing applied for fome time; as we fee in Plaifters and Unguents P.

(5.) There is nothing found hot to the human Touch in the Parts of Animals after Death, or after Separation from the Body. Even Horfe-dung retains not its Heat, unless it be prefs'd together and buried, yet all Dung feems to have a potential Heat, as appears from Compofts and Manuring. In like manner, the Carcafes of Animals have a latent and potential Heat; infomuch that in the Church-yards where Burials are frequent, the Earth collects_a_certain Heat, which confumes a Carcass newly laid in it, much fooner than mere Earth 9. And 'tis reported that the People of the Eaft have a certain fine, foft Cloth, made of Birds Feathers, which by its native Heat will diffolve Butter, gently wrapt up therein.

(6) Those

"See above, Tab. II. §. (26.) Confider alfo of the spontaneous Heating of Marcafites with Water; Iron Filings and Sulphur, moiften'd with Water; and other Inftances

of this Nature.

• Tab. I. §. (18.) and Tab. II. §. (24.)

P Thus the Emp. Epifpaftic. Emp. Stomachic. magistral. Emp. è Cymino. Ung. Martiat. Ung. Maftichin. &c. are heating; and Emp. de Ranis cum Mercurio, Emp. è Cicuta; Ung. Nutritum, Ung. Populnaum, &c. are cooling.

9 Is the Fact fufficiently verified?

This may require farther Confirmation.