The Shrinking of Bodies. Whence the drive them before it; fo as to make them iffue at the fame time: whence .proceeds Ruft, and the like ". 167. But the Contraction of the tangible Parts, after fome of the Spirit is difcharged, upon which Drinefs enfues, is made fenfible by the increased Hardnefs of the Body; but much more by the fubfequent cracking, or fplitting of the Body; and the contracting, wrinkling, and and overwrapping of the Parts. Thus the Parts of Wood crack, or fplit afunder, and are contracted; Skins wrinkle; and if the Spirit be fuddenly forced out by the Heat of Fire, they fhrink so fast as to curl and roll themfeves up, &c. 168. On the other hand, where the Spirit is detained, and yet dilated different Ef and excited by Heat, or fomething analagous thereto, (as happens in the fects of Heat. more folid or tenacious Bodies) then the Body is either foften'd, as in the Cafe of ignited Iron; or flows, as in melted Metals; or liquifies, as in diffolved Rofin, Wax, &c. therefore thefe contrary Operations of Heat, hardening fome Bodies, and liquifying others, are eafily reconciled; because in the firft Cafe the Spirit is driven out; but agitated and detained in the fecond: the latter being the proper Action of Heat and Spirit; and the former the Action of the tangible Parts, fucceeding. upon the Emiffion of the Spirit. The Formation Bodies. 169. But where the Spirit is neither quite detain'd, nor quite difof Organical charged; but only attempts and tries to force its Prifon; and readily meets with fuch tangible Parts as will obey, and yield to its Motions; fo that wherever the Spirit leads, they follow it; then it is that an organical Body is formed; with its diftinct Parts, or Limbs; and that all the vital Actions enfue, as well in Animals as Vegetables. How brought 170. And these Operations are principally brought down to the Senfe,down to Senfe. by diligently obferving the firft Beginnings, Rudiments, Strugglings, or Tendencies towards Life, in the little Creatures bred from Putrefaction; as in the Eggs of Ants, in Worms, Flies, Frogs after Rain, &c. For there are required to Vivicafition, both Gentlenefs of Heat, and Tenacity of Body; that the Spirit may neither break forth too haftily; nor be too much confined, by the Stubbornness of the Parts; but rather be able to mould and fashion them, like Wax. Three different 171. Again, that noble Difference of the Spirit, which has regard Kinds of Spi- to fo many Things, is brought and fubmitted, as it were, to View, by rits in Bodies, found by Reduction. numerous Ruft, is now ufually fuppofed to be occafioned by the external Air, or fomething_contained therein, that preys upon, and in part diffolves the external Surface of the Metal. Here then is what the Author calls a Cross-Road, that requires a Crucial Inftance. Let Trial, therefore, be made, whether Iron will ruft in an exhaufted Receiver. And, by the way, let not the Examples here produced, as Illuftrations of the Doctrine of Prerogative Instances, be fuppofed any way intended as Decifive their Defign being rather logical than philofophical; fo as to fhew the way of profecuting Enquiries; and not themfelves to ferve as Enquiries. And in this View fee the feveral regular Enquiries of the Author in the third Volume. : * See Vol. III. p. 556, &c. numerous Summoning or Reductory Instances. This Difference, we mean, is that of the truncate Spirit, the Spirit fimply ramous, and the Spirit both ramous and cellulous: the first whereof is the Spirit of all inanimate Bodies; the fecond the Spirit of Vegetables; and the third the Spirit of Animals . 172. In like manner, it appears, that the more fubtile Textures and The more fubStructures of Things, (tho' vifible and tangible in their entire Bodies,) are tile Textures neither feen nor felt; and, therefore, in thefe alfo the Bufinefs of Infor- made fenfible by Reduction. mation proceeds by Reduction. But the moft radical and primary Difference of Structures, is taken from the greater or lefs Quantity of Matter contained in the fame Space or Dimenfion: for the other Structures depending upon the Diffimilarity of the Parts contained in the fame Body, and their Situations, are but fecondary, in refpect to those. 173. Thus, let the Subject of Enquiry be the Expansion or Contraction The Density of Matter in Bodies, respectively; to difcover what Quantity of Matter and Rarity of Bodies. fills what Quantity of Space in each. Now, there is nothing truer in Nature, than thofe Twin-Propofitions, that Nothing can never make Something; and that Something can never be reduced to Nothing: but the entire Quantity, or total Sum of Matter in the Univerfe, ftill remains the fame, without Increafe, or Diminution. 'Tis alfo as certain, that a greater or lefs Quantity of Matter is contain'd under the fame Space, or Dimenfions, according to the Difference of Bodies. Thus Water contains more Matter than Air: whence to affert, that an equal Bulk of Water is convertible into an equal Bulk of Air; is to affert, that fomething is reducible to nothing: as, on the other hand, to affert, that a certain Bulk of Air may be turned into an equal Bulk of Water; is the fame, as to affert, that fomething may be made out of nothing. And from this greater or lefs Quantity of Matter, thofe Notions of Denfity and Rarity, which are variously and promifcuoufly received, may be corrected, or new ones juftly derived. 174. It must be likewife allowed as certain, that this greater or lefs That the diffeQuantity of Matter we fpeak of, contained in Bodies, may, by Compa- Gravities of rent Specific rifon, be brought to Calculation; and the exact, or nearly exact, Pro- Bodies are deportion determined. Thus, for Example, we fhould not greatly differ terminable. from the Truth, to fay, that a given Bulk of Gold contain'd about two and twenty times as much Matter, as an equal Bulk of Spirit of Wine; or that a Bulk of Spirit of Wine equal to the Bulk of Gold, muft poffefs about two and twenty times as much Space as the Gold *. 175. But See the Sylva Sylvarum, paffim. 8 See the History of Life and Death, paffim. h See Vol. III. p. 505, &c. On this is founded the Ufe of the Hydrostatical Balance. See the Author's Hiftory of Con denfation and Rarifaction, paffim. See the Author's Table of the Specific Gravities of Bodies, Vol. III. p. 512, 513. The Denfity of 175. But the Denfity of Matter, and the Proportions thereof, are Matter made made fenfible by Weight; for Weight correfponds to Quantity of fenfible by Matter; with regard to the tangible Parts of Bodies: but Spirit, and Weight. its Quantity of Matter, is not cognizable by the Balance; because it rather diminishes than increases Weight'. And, with this View, we have made a TABLE, to fhew the specific Gravities, or Weights and Bulks, of all the Metals; the principal Stones, Woods, Liquors, Oils, and many other Bodies, as well natural as artificial ". And fuch a Table we judge to be of infinite Ufe; as well to procure the Light of Information, as to ferve for a Rule in Practice; and again to discover many Particulars, that would have been abfolutely unexpected ". A Table of the specific Gravities of Bodies. Its Ufe. Bodies. 176. It is no fmall Advantage of this Table, to demonftrate, that all the Variety found in the numerous tangible Bodies known to us, (which are compact, and neither spongy, hollow, nor in great part filled with Air,) exceeds not the proportion of twenty-two to one. So finite a Thing is Nature; at least that Part thereof whofe Ufe principally regards our felves P. An Attempt to 177. We also thought it worth trying, to difcover the Proportions of difcover the untangible, or pneumatic Bodies, with refpect to fuch as are tangible: Proportion be for which purpofe, we took an Ounce Vial; chufing it fmall, that the twixt tangible and untangible following Evaporation might be performed with the lefs Heat. This Vial we fill'd almoft to the Neck, with fuch Spirit of Wine as we obferved by the Table, mention'd above, to be fpecifically lighter, or to contain lefs Matter under the fame Dimension, than all other tangible Bodies that are close and compact. Then we exactly mark'd down the Weight of the Spirit, and the Vial together. After this, we took a Bladder, containing about a Quart, and fqueez'd all the Air out, as near as poffible; till the Sides of the Bladder collapfed, and became contiguous; having firft gently oil'd it, to render it the clofer or tighter, by filling up the Pores, if there were any. This Bladder we strongly tied with a Wax Thread about the Neck of the Vial; putting the Mouth of the Vial into the Neck of the Bladder: then fetting the Vial upon a Chafing Dish of warm Embers, the Vapour of the Spirit, dilated by the Heat, and thus render'd pneumatical, gradually diftended or fwell'd out the Bladder every way, like a Sail. Then we immediately remov'd the Glafs from the Fire; and placed it upon a Carpet, to prevent its breaking by the Cold: and now we directly made a Hole in the upper Part of the Bladder, left the Vapour, as the Heat diminish'd, should fall back, or condenfe into Liquor, and disturb the Calculation. Then See above, §. 165. m See Vol. III. p. 512, &c. n See Vol. III. p. 519, &c. taking Suppofe the Difference in fpecific Gravity between Gold and Spirit of Wine. above, $. 174. See alfo Vol. III. p. 512, 513, 517. P Viz. The tangible Part. See taking away the Bladder, we weigh'd the remaining Spirit of Wine; and thence computed how much was wafted in Vapour: and, by comparifon, calculating how much Space the Body poffefs'd in the Form of Spirit of Wine in the Vial; and again, how much it poffefs'd when render'd pneumatical in the Bladder; it plainly appeared, that the Body, fo converted and changed, acquired a Degree of Extenfion a hundred times greater than it had before. Heat or Cold, 178. In like manner, let the Nature fought be Heat or Cold, fo weak Imperceptible in Degree as to be imperceptible. Thefe are brought to the Senfe by means of a Weather-Glafs, fuch as we have above defcribed; wherein Heat Senfes by the brought to the expands, and Cold contracts the Air. Neither is this Expanfion and Thermometer. Contraction of the Air perceptible by Sight; but the Air, when expanded, depreffes Water; and, when contracted, raifes it up: and thus alone it is that the Thing becomes visible, and fenfible; and not otherwife. 179. In like manner, let the Subject of Enquiry be the Mixture of The Mixtures Bodies; to determine what they contain that is aqueous, oleaginous, fpi- of Bodies, or the Properties rituous, faline, earthy, &c. or, in particular, how much Butter is con- of their diffe tain'd in Milk; how much Curd, how much Whey, &c. All these rent Parts. Things are reduced and brought down to the Senfes by artificial and fkilful Preparations, exhibited in the Form of tangible Bodies'. But the Nature of the Spirit in them, tho' not immediately perceived, is difcover'd by the various Motions, and Endeavours of tangible Bodies, in the Act and Process of their Separation; as also by the Acrimony, Corrofiveness, different Colours, Smells and Taftes of the fame Bodies, after Separation. 180. And, with regard hereto, Men have beftowed great Pains The erroneous upon Distillations, and artificial Separations; but not with much betProcedure of the Chemifts ter Success than in the other Experiments hitherto practifed: as hav- berein. ing proceeded altogether by feeling out their Way in blind Roads; or with more Labour than Understanding; and, what is worfe, without imitating, copying, or rivalling Nature: but by their violent Heats, and overpowerful Operations, deftroying all the Subtilty of Structure, in which the fecret Virtues and Relations of Things are principally feated. Fire. 181. Nor have Men, as we elsewhere observed, hitherto taken No- Alterations tice, with regard to this kind of Separations, that numerous Qualities, in caused by the the torturing of Bodies, as well by Fire as otherwife, proceed from the Fire itfelf; and the Matters employ'd in the Separation; which Qualities were not before in the Compofition: whence ftrange Fallacies have arifen. Thus all the Vapour which Water emits by Fire, is not the Vapour, or Air, before exifting in the Body of the Water; but in great measure • Aph. 13. As in all thofe called Chemical Analyfes, or Refolutions. Hence there are few genuine Separations to be found in the common Chemistry; even as practifed by the beft Hands. See the Sylva Sylvarum, under the Article Geld, &c. See above, Part II. Aph. 7. and the Sylva Sylvarum, paflim. Adulterations measure produced by the Dilatation of the Water, thro' the Interpofition of the Heat of the Fire. 182. So likewife, in general, all exquifite Trials and Examinations of in Bodies to be Bodies, whether natural or artificial, made to diftinguish the genuine Sought. from the adulterate, and the better from the worfe, fhould be referred to this Head; as thefe alfo make what is infenfible to appear fenfible: and therefore are, with great Care, to be collected from all Quarters ". The Motion of either too Swift, or too flow. How reduced 183. As to the fifth Way of Concealment from the Senfes ; 'tis manifeft that the Action of Senfe is performed in Motion, and Motion in Time; whence, if the Motion of any Body be either fo flow, or fo fwift, as not to be proportion'd to the Moments wherein the Act of Senfation is performed, the Object will not be perceived; as we find in the Motion of the Hand of a Clock; and the Motion of a Bullet difcharged from a Gun. 185. But the Motion which is not perceived thro' its Slownefs, is to the Senfes. eafily and commonly reduced to Senfe, by the Refult or Amount of the Motion: but that which is imperceptible thro its Velocity, is not hitherto well measured; yet the Enquiry of Nature demands that this fhould be done in fome Cafes *. How Reduction 186. In the fixth Cafe, where the Senfe is hinder'd by the too great is made, where Power of the Object', Reduction is made either (1.) by removing the the Object is Object farther from the Organ of Senfe; or (2.) taking off from its too powerful. Force, by the Interpofition of fuch a Medium as may weaken, but not annihilate it; or (3.) by admitting and receiving the Reflexion of the Object, where the direct Force of it is too strong; as by receiving the Reflection of the Sun in a Bafon of Water. Where the Senfe is full charged. Reduction fometimes made to the Senfe of other Animals. 187. The feventh Cafe of Concealment from the Senfes, (viz. that wherein the Senfe is fo full charged with the Object, as to leave no room for the Admiffion of a new one,) is almoft wholly confined to the Senfe of Smelling, and Odours: and does not confiderably regard the Subject in hand. So that thus much may fuffice for the Business of reducing infenfible Things to fuch as are fenfible. 188. Sometimes alfo Reduction is made, not to the Senfe of Man, but to the Senfe of other Creatures, whofe Senfations, in fome Particulars, exceed thofe of Men; as the Senfation of a Hound, in fome Kinds of Smell; and the Senfations of a Cat, an Owl, &c. which fee Things in the Night by the latent Light of the Air, which is not externally illuminated. For Telefius has juftly obferved, that there is a certain original Light in the Air itself; tho' fmall, faint, and generally unferviceable, "See Mr. Boyle's Medicina Hydroflatica; and the de Augmentis Scientiarum, p. 46. w See above, §. 158. * Thus the Motion of Sounds, and even of Light, which feems the fwifteft Motion of all, is now reduced to Calculation. See the Author's History of Sounds, in the Sylva Sylvarum ; and Sir Ifaac Newton's Optics, and Principia, paflim. y See above, §. 158. |