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Show VE VE does not confift of fibrous Particles wound up like little Springs; but of Particles that do not touch one another, but have a repellent Forcé, which is reciprocally proportionable to the Diftances of the Particles, agreeable to what Sir J/aac Newton fays in his Opticks, ry 31. “he Particles when they are fhakenoff from Bodies by Heat or Fermentation, fo foon as VE Lungs, through four Diaphragms of Flannel , dipp'd in a Lixivium of highly calcin’d Salt of Tartar, and afterwards dry’d, and blowing back the fame Air in {uch manner, that it ma ts at every Infpiration, return throughthe frid Diaphragms ; which is done by Means of two Valves. The Moifture and fulphureous Va- pours of the Air, are, by this Contrivance, ftopp’d in pafling through the Flannel, and they are beyond the Reach of the Attraction thereby the Air continues wholefome much of the Body, receding from it; as alfo from longer than it would in the common Way of one another, with greater Strength, and keeping at Diftance fo, as fometimes to take above a Million of times more Space than they did before in the Form of a denfe Body ; which vaft Contraction and Expanfion feem unintelligible, by feigning the Particles of Air to be {pungy and ramous, orroli’d up like Hoops, or by any other Means than bya repulfive Power. Our Author made fome Experiments upon a Calf’s Lungs, which help to confirm Dr. Fames Keil’s Affertion, viz. That the inner Surface of a Man’s Lungs is equal to about 150 {quare Feet, which is about 10 times more than the Surfacc of the whole Body. ‘Then, by feveral Experiments and curious Obfervations, found, that of the Air whichis infpir’d by the Lungs in an Hour, (wiz. 48000 cubick Inches) about 353 Inches, or 100 Grains in Weight, are deftroy’d in that Time. He fhews that the Reafon that fulphureous Air is pernicious, is, becaufe it lofes its Ela- fticity fo faft, that the Lungs will fubfide in it, and the Blood confequently ftagnate. He concludes, that when the Particles of fuch Air are united into pretty large Molecule, in a fix’d State, they are too big to enter into the Veffels of the Lungs. He fhews the Miftake of thofe, that fupposd the Air did not lofe its Elafticity, but its vivifying Spirit, by Vapours, by an Experiment made upon a Dog, into whofe Lungs he drove byForce, that effete Air, which the Dog, by his own Aétion, could not draw into his Lungs; and whereas the Dog then was juft expiring by the Subfiding of his Lungs, he kept him alive by the forcible Impulfion of that very Air, as long as he could blow up the Dog’s Lungs withit. He makes it appear, that a clofe, warm Air, without a Communication with the outward Air, to carry off the Vapours, muft be unfit for Breathing long, and therefore condemns the Ufe of GermanStoves. That when Animals are kill’d by Lightning, without any vifible Wound, it is becaufe the fulphureous Steams have deftroy’d the Elafticity of the Air about them: As appears by diffe&ting fuch Animals, whofe Lungsare always found comprefs'd together, without any Air in them. ‘The fame alfo appears in Men that have been kill’'d by Dampsin Mines. Then he gives the Defcription of an Inftrument, whereby fouror five Quarts of the fame Air (which, in the common Way, can 7 one Manto breathe verylittle above a nute) may ferve 8+ Minutes to breathe, by drawing in the Air, which has been in the Breathing: ‘This he propofes as ufeful to thofe who have Occafion to go into Places where the Air is infectious ; but where the noxious Vapours are not very denfe, Mufflers only of Cloth or Flannel, impregnated with Salt of Tartar, may ferve ; as he found by feveral Experiments, He thews afterwards the Reafons why Pulvis Fulminans has more Force than Gun-powder, and confirmsSir I/aac Newton’s Account of Fire and Flame, (Query 9 and 10 of his Opticks) but fhews Dr. Newentyt’s, Dr. Boerbaave’s, and Monf: L’Emery’s Account of Fire to be erroneous; but that it was not the Matter of Fire, but elaftick Air, which that laft nam’d Gentleman had {0 often obferv’d to be loft in the Analyfis of Bodies, That the Artificial Sulphur made by Monf, Geoffrey was inflammable, chiefly on account of the Air fupply’d to it by the Oil of ‘Tartar. Thatif Fire was a peculiar Matter,it ought to dilate, not to condenfe the Air; as it ap- pears to do by Experiment. ‘That Fire confifts in the Action and Re-aétion betweenrepellent Air and attracting Sulphur ; and that Heat is communicated by the ztherial Medium mentioned by Sir J/zac Newton in the laf Edition of his Opticks, That Fermentation will diffolve Bodies without the Help of included Fire, acting according to its feveral Degrees; a lower Degreeof it Cfuch as attends every inteftine Motion) not being inconfiftent with the healthy State of Plants and Animals. That acid Particles, by their great attractive Force, diffolve Bodies rufhing towards their Particles, fo as to excite Heat, and fhake afunder fome of them, and turn them into Air. ,, That Air in a fix’d State is the Bondot Union, which makesSalts durable, and w f keeps together the folid Parts of Veg Animals, and even Globules of the Blood. That the Air, in a moift State, is foonel abforb’d by fulphureous Steams thanina dry State; for a Candle, which in a dry Receive! burn’d 70 Seconds, burn’d but 64 in the fame Receiver, when it was fill’d with the Fumesof hor Water; but yet abforb’d 5 Pa more of Air. But the abforbing Subtta lofe the Force of Aéting, when unite large Body ; Brimftone in a Roll abforb Air, tho’it doesit fo plentifully, when re into minute Particles, : That fome of the Food of Ani rates, and fome abforbs Air, ftion in a healthy State is beft } there is but a little more Air generated than is abforb’d, From the Confideration of the feveral Experiments made by Mr. Hales, in his Analy/is of Air, he makes it appear, that our Atmo{phere is a Chaos ofdifferent Particles ; fome of which are elaftick and fome unelaftick ; and that the elaftick Parts are endued with very different Degrees of Elafticity, according as they are bigger or lefs, more or lefs folid, more orlefs watry ; and therefore, that fome are eafily, and fome moredifficultly reducible toa fix’d State. That it is chiefly by the Change of Air, from a fix’d to an elaftick, and from anelaftick to a fix’d State, that this beautiful Zrame of Things is maintain’d in a continual Round of the Produétion and Diffolution of animal and vegetable Bodies ; and therefore, that there is asmuch Reafon to adopt Air among the chy-~ to the Air i ads, as int Spiders and Silk- woris. He fhews that the Pith ferves to fupply the dilating Moifture for the tender Shoots ; but that their Figure may be oblong, and not round, as the Fruit commonly is; there are tough Diaphragms in the Pith, at {mall Diftance from each other, which check the lateral Expanfion ; as alfo horizontal Fibres, which ferve for the fame Purpofe: And of the fame Sort is the Pith in the large growing Feathers of Birds; which is made up of Veficles, that can be diftended lengthwife, but have Splinters at the Ends, to prevent too great a lateral Dilatation. That the Bones of Animals do not growat the Joynts, (which would prevent their free Motions) but at the Symphyfis, viz. where the Heads join to the Shanks of the Bones. That there are particular Veffels in Vege- tables, as well as Animals, appropriated for conveying different Sorts of Nutriment; and that where avifcid Subftanceis to be furnithed, VII. The Author in this Chapter applies his the Veffels are {engthened, andoften fetch a everal Experiments and Conclufions drawn from Compafs to retard the Velocity of the Pluid, hem, to Vegetation ; and fhews chiefly the fol- which is to be infpiffated into a hard Subowing Things, viz. That V tables are com ftance. Thus in hard Stone-Fruits the umbipos’d of Sulphur, Volatile Salt, Water, Earth, lical Veffel goes round the Concave ofthe Stone, and then enters the Kernel near its and Air. Cone. That in Nutrition, the Sum of the attractThenat laft he traces the Vegetation of a ing Powers of thofe Subftances is fuperior to the Plant, from a Sced to a Tree again producing Sumoftherepellent ; and as the watryVehicle Seed ; which Account, as it cannot well be flies off, the Parts harden. contracted, without leaving out fomething maThat Oil which is made up of Sulphur terial; and as it ferves to fhew fome ofthe and Air, abounds in Seeds for their better excellent Ufes of his py Difcoveries, it fhall be given in his own Words. Prefervation. That in cold Countries, where thofe PrinSupported by the Evidence of manyof the ciples are not fo firmly united, fmall Wines foregoing Experiments, 1 will now trace the fuch as Rhenifv, mutt eafily yield their Tartar, Vegetation of a Tree, from its firft feminal Plant which by Experiments appear to contain Oil in the Seed, toits full Maturity and Produétion \ir) ; but generous Wines, fuch as Madera, of other Seeds, without entering into a parting thofe Principles more firmly united, cular Defcription of the Structure ofthe Parts will bear a great Degree of Heat before they of Vegetables, which has already been done byDr. Grew and A bi. part with them. Wefee by Ex nent, 56, 57, 58, on That the Ufe of the Leaves of Trees, is to g up Nourifhment within the Reach of the diftill’'d Wheat, Peafe, and Muftard feed, whac ration of the Fruit, to carry off the re- a wonderful Provifion Nature has made, that it watry Fluid; to imbibe Rains and the Seeds of Plants fhould be well ftored with s which are impregnated with Salt and very active Principles; which Principles are Sulphur; as likewifé to imbibe Air, and to be there compacted together by Him, who curiof the fame Ufe to Plants, as Lungs are to oufly adapts all Things to the Purpofes for which theyare intended, with fuch a juft DeAnimals. Thefe Plants which are overfhaded, or too gree of Cohefion, as retains them in that replete with Moifture, cannot fo well imbibe State “till the proper Seafon of Germination: Air; therefore, tho” they will fhoot out faft, For if they were of a more lax Contftitution, and have much Weod, they will be more bar- they would too foon diffolve, like the other tender annual Parts of Plants; andif they ren in proportion. mical Principles, as acid Sulphur, tho’ it has hitherto been rejected by the Chymitfts. He alfo, by a very ingenious Contrivance, found the Degrees of growing in every Part of young Shoots, which in their gro tend themfelves moft in the Middle, and leaft towards the Top and the Bottom; the ductile Matter for their Growth being drawn out in Length, like melted Glafs Tubes, which ren a Hollownefs, though drawn out to the fnalleft Thread were more firmly connected, as in the Heart of an Oak, they muft neceffarily have been many Years in germinating, though fupply’d with Moifture and Warmth. Whena Seed is fown in the Ground, ina few Days it imbibes fo much Moifture, as to {well with very great Force; as we fee in the Experiment on Peafe in aniron Pot. This forcible fwelling of the Lobes of the Seedar, ar (Fig.1.) does probably protrude Moifture and Nourifbment from the capillary Veffels rT 15 |