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Show The Anatomy 5. §. BookI. Frombence, it alfo appears, That the Pith is of rt Subftantial Nature with the Parez hyma of the Bargue, and wit 1 the Diametral Portions 3 and that thereforethey are all one body, differ ing in no Effential Property, but onlyin their Shape and Place. The fame is alfo evident from the Continuityof the Pith with the Diametral Portions, as of Thefe, with the faid Parenchyma. And from their Contexture, which, by a Microfcope, appeareth to be of one and the fame general kind, in all Plants, both in the Perencleaa pe the Barque, in the Ixfertment or Diametral Portions, and in the Pith, all being made up of Bladders. 6. g. T2b.9,& 15. The Bladders of the Pith, are of very different Sizes 5 fel- dom lef, than in the Bargue, as in Afparagus; ufually much bigger, asin Horfe-Radifh. They may be well reckoned to about fifteen or twenty degrees; thofe in Ferufalem Artichoke, Ona largeft 5 in Valerian, Horfe-Radifh, of the meaner5 in Biftort, Peony, of the fmalleft. Their Pofition is rarely varied, as it is oftentimes, in the Bargue $ but more uniform, and in¥hetranfverfe Cut, equally refpective toall parrs of the Rost: yet being piled evenly, one over another, in the long cut, they feem to run, in Dire& Trains, by the length of the Root. Their Shape alfo is, uftally more orbicular; but fometimes, fomewhat angular, inthe larger kinds, as in Ferufaleme Artichoke. ' 1 ip J i ih bil sinh Bayes +ti 7. §. THUS FAR the Contexture of the Pithis well difcoverable in the Root. In the Tru#k, farther, and more eafily. Whereof therefore, in the next Book , I {hall give a more particular Defeription and Draught. Yet fince I am {peaking of it, I fhall not wholly omit here toobferve, That the sides, by which the aforefaid Bladders of the Pith are circumfcribed, arenot meer Paper-Skins, or rude Mem- branes but fo many feveral Ranks or Piles of exceeding fmall Fibrous Threds; lying, for the moft part, evenly one over another, from the bottom to the top of every Bladder; and running crofs, as the Threds in the Weavers Warp, from one Bladder to another. Which is to fay, That the Pith isnothing elfe but a Retewirabile, or an Infinite Number of Fibres exquifitely fmall, and admirably Complicated together: as by cutting the Pith with a Razor, and fo viewing it with a good Gla/t, may be feen. See the Figures belonging to the Third Wook. &. §. All Plants exhibit this Spectable, not alike diftin@y ; thofe beft, with the largeft Bladders. Nor the fame Pith, in any condition; but beft, when dry : Becaufe then, the Sap being voided, the {paces betwixt the Fibrous Threds, and fo the Threds themfelves, are more di{tinctly difcernable. Yet is it not to be dryed, after Cutting, Becaufe its feveral parts, will thereupon coincide and become deformed. But to be chofen, while the Plazt is yet growing 5 at whichtime, it may be often found dry, yet undeformed 3 as in the Trunks of Common Thiftle, Ferufaler Artichoke, &c. ; ; 9. §. Neither are thefe Threds, fo far as can obferve, Single F7Fires, but ufually, confift of feveral together. Nor are they imply Collateral, but by the weftage of other Fibres, in their natural Eftate, knit together 5 muchafter the fame manner as the Spiral Fibres of the er Hh) i f i J i i it M BookIL. of Roots, Aer-Vefféls. This Connexion I have no where {0 well feen, as in the White Bottoms of the Bladders ofa Bulrufh, being cut traverfe ;- wherein they have the appearance, ofvery Fine andclofe Needle-work, 10. §. The Fibres by which the faid Threds are knit together, I think are all Single : and are feldom and {carcely vifible, except by obliquely Tearing the Pith ; by which means, they will appear through the Glafs, broken off, fometimes, a quarter or half an Inch, or an Inch in Length; and as fmall as one Single Thred ‘of a Spiders webb. In a Bulruh, they are fometimes difcernable in cutting by thé Length. Thefe Fibres, and the Threds , they knit together, for the moft part, are fo pellucid, and clofély fituate, that they frequently fem to make One entire Body, as a picce of Ice or a film of Water it felf: or even as Avimal skins fometimes thew, which yet are known to be Fibrous. : 11. §. The Situation of thefe Threds, is contrary to that of the Vefféls, as thofe by the Length, fothefe, chiefly, by the Bredth of the Root,or horizontally, from one edge ofthe Pith to the other. They are continued circularly ; whereby, as oft as they keep within the compa of the feveral Bladders, the {aid Bladders are Round: But where they winde out ofone Bladder, into another, they mutually Interfeé a Chord oftheir feveral Circles ; by which means, the Bladders become AnguJar. 12. §. The Contexture, likewife, both of the Parenchyntous Part of the Barque, and ofthe Diametral Portions inferted betwixt the Ligvous 5 isthe fame with this ofthe Pith, now deferibed ; that is, Fibrous. Whence we underftand, How the feveral Braces and Threds ofthe Ve Jféls are made: For the Vefels running by the length of the Root, as the Warp 5 by the Parenchymous Fibres running crofs or horizontally, as the Woof: they are thus Avit and as it were fiitched wp together. Yet their wefiage feemeth not tobe fimple, asin Cloath ; but that many of the Parenchymous Fibres are wraped round about each Veffel ; and, in the fame manner, are continued from one Veffel to another ; thereby knitting them altogether, more clofély, inte one Tubulary Thred s and thofe Threds, again, into one Brace: much af ter the manner. of the Needle work called Back-Stitch or that ufed in Quilting of Balls. Some obfcure fight hereof, may be taken ina Thred ofCambrick, througha Microfope. But it is moft vifible, inthe Leaves and Flowers of fome Plants, The Delineation ofthefe Things [ hal! therefore omit, till we come hereafter to {peak ofthe other Parts. 13. §.. From what hath been faid, it may be conjectured ; That the Aer Veffels facceffively appearing in the Barque, are formed, not out of any Fluid Matter, asare the original ones: Butofthe Parenchymous Fibres fe. by changing them from a Sphericalto a Tubulary Forme, 14. §. From the precedents, it is alfo manifeft, That all the Parenchymous Parts of a Root, are Fibrous. 15. g. And laftly, That the whole Body of a Root, confifteth of Veffels and Fibres. And, That thefe Fibres themfelves, are Tubulous, or, |