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Show Book I of Plants. Se The Anatomy bly extended by the length of the Ph; but are really difcontinuous and fhort, and as ‘tis faid, fomewhat anfwerableto the Gells of an Hony-Comb. This is the neareft wecan come to them, by the bare Eye witt liftance of a good Micro cope. Mr. Hook fheweth in his M Ay, That the Pores of the Pith, particularly of Elder-Pith, fo far as theyare vifible, are all alike difcontinuous ; and that the Pith is nothing elfe but (as he calls them) an heap of gxbbles, Although, in regard they are not fluid, but fixed Parts, I thall lated. And this being dilated, the Cortical Body alfo, muft needs be izferted ; and is therefore in proportion always, more or lefs, fmaller here in the Trazk, than inthe Root. And as the Cortical Body leflens, fo the Pith will be enlarged, and by the fame proportion is here Tab. 3. fr 6 Glafs, in a piece of Burdock , See in Tab, 3. _ But a more "pats greater. Andthe P7th being enlarged it fel, its Pores ( the Lignoms Body, uponits dilatation, as it were tentering andftretching out all their fides) muft needs likewife be enlarged with it; andaccordingly, are ever greater in the Pith of the Traxk, than of the Roay. And the dilatation of the Lignous Body {till continued, it follows, that whereas the Pith defcendent in the Rovt, is not only in propor- -2. $3516, farther confirms what in the Second Chapter we have faid of the times higher, altogether abfent: Contrariwife, in the Trunk, it is not only continuedto its top and fmalleft Twigs, but alfo there, in proportion, equally ample with what it is in any other inferiour choofe rathertocall t , Bladders. ; As they appear through a good ticular Defeription of the Si Figures, and admirable Textures hereof, I have given in feveral places in the following Books. * 19. §. Befides what this Obfervation informs us of here, it Original of the Pith and Cortical Body, and of the famenefs of - thing elfe but a Mafs of Bladders; as inthe Firft Chapter hath been eo, faid. 20. §. Inthe Piths of many Plants, the greater Pores or Bladders have fome of them leffer ones within them, and fome of them are divided with crofs Membranes: And betwixt their feveralfides, have, I greater, fo this; asin Herbs is common; the Lignous Body being ufually fo far. dilated, that the utmof? Shootings thereof may eafily be think, other fmaller Bladders vifibly interje@ed. However, that theyare all permeable, is moft certain. Theyftand together not confufedly, but in even Ramks or Trains 3 as thofe of the Infertions by the breadth, fo thefe by the length of the Trak, And thus far there isa general correfponding betwixt the parts of the Root and Trunk, Yet are there fome confiderable Difparities betwixt them; wherein, and how they come to pafs, and to what efpecial Ufe and End, fhall next be faid. An Account the Growth of the Trunk. art. f 23. §. But although the opennef$ of the Aer permitting, be allways alike; yet the Energy ofthe Sup effecting, being different ; as therefore both their natures with the Parenchywa of the Seed: which is no- of tion lefs and lefs, but alfo in the fmaller extremities thereof, and fome- that doth, the dilatation of the Trunk , will alfo vary. If that be lefs, fo is this; as inthe Trwwks of molt Trees: IF that be feen to jut out, and adjoyn tothe Skiz. And if the Sap be ftill of greater energy, it fo far dilates the Ligwous Body, as not only to amplifie the Pith andall its Pores; but alfo fo far to ftretch them out, as to make them tear. Whereupon either running again into the Cortical Body, or thrinking up towards it, the Truk thus fometimes becomes an AaHow Stalk, the Pith being wholly, or in part voided. But generally it keeps entire; and whereit doth, the fame proporti- lation alfo _)duly prepar'd; the prime part thereof pafling through the intermediate Coardure,in due moderation and purity is entertaind at laftinto the Truzk, And the Sap of the Trunk being purer and on and refpect to the Lignous and Cortical Bodies, as is faid. The Confequences of all which will be, the Strength of the Truwk, the Security andPlenty of the Sap, its Fermentation will be guicker, its Djferibution moreeffectual, and its Advancement morefufficient. 24. §. Firft, the Erect Growth and Strength of the Trunk; this being, by the pofition of its feveral Parts,effected : for befides the flendering of the 27umk {till towards the top, the Circumferential pofition likewife will be more noble, receiving a difpofition and tendency to afcend therewith. And what bythe sap the Trunkis in part dipos'd ent. So that as the Lignous, Body, inthe fmaller parts, of the Root ftanding Central, we may thence conceive and fee their pliablenefs to 21. g. WE SAYthen, that the sap being in the Root by Filtra- tions, Fermentations (and in what Roots needful, perhaps by Circu- more volatile, and foit felf apt to afcend; the motion of the Trunk to, bythe refpective pofition and quantity of its Parts it is effeQually enabled. For whereas in the Root the Ligwous Body being in proportion with the Cortical, but little, and all lying clofe within its Centers it muft therefore needs be underits controul : on the contrary, being here comparatively ofgreater quantity, and alfo more dilated,and having divers of its Branches {tanding more abroad towards the Circumference, as both in the Leaves and Bodyof the young Truzk and Plume, is feen; it will in its own magnetical tendency to afcend, of the Lignows Body, likewife is, and that eminently, hereunto fubfervi- anyoblique motion ; fo here, on the contrary, the Lignous Body ftan- ding wide, it thus becomes the Strength of the Truzk, and moft advantageous to its PerpendicularGrowth. We fee the fame Defign in Bones and Feathers: The {trongeft Bones, as thofe in the Legs, are hollow. Now fhould we fuppofe the fame Boxe, to be contraéed into a Solid; although nowit would be no heavier, and in that refpect, asapt for motion ; yet would it have far le {trength, than as its Parts are dilated to a Circumferential pofture. Andfo for Quills, reduce the Cortical Body to a compliance with it, which, for the fame Reafons, in fubferviencyto flying, as they are exceeding light 5 So, in comparifon with the thinnefs oftheir Sides, they Groundin the openAir, the difpofition ofits Parts, originallydifferent Solid Cylinder. 22. g. And the Truvk thus {tanding from underthe reftraint of the from that ofthe Parts in the Root, will not only be continued, but improved. For bythe force and preffure of the Sap inits collateral Motion, the Lignons Body will now more freely and farther be . lated. are very ftrong, and much lef apt to bend, than if contracted into 2 We fee it not only in Nature, but Art. For henceit is, that Foyners and Carpenters unite and fet together their Timberpieces and feveral Works oftentimes with double Joynts 5 which, although = |