Having examin’d and pursu’d the Degrees of Vegetation in the Seed, we find its two Lobes have here their utmost period; and, that having conveyed their Seminalities into the Radicle and into the Plume; these therefore as the Root and Trunk of the Plant still survive; Of these in their order we next proceed to speak; and first, of the Root: whereof, as well as of the Seed, we must by Dissection inform our selves.

In Dissection of a Root then, we shall find it with the Radicle, as the Parts of an old man with those of a Foetus, substantially one. The first Part occurring is its skin, the Original whereof is from the Seed: For that extream thin Cuticle which is spred over the Lobes of the Seed, and from thence over the Radicle, upon the shooting of the Radicle into a Root, is co-extended, and becomes its Skin.

The next Part is the Cortical Body; the Original whereof likewise is from the Seed; or the Parenchyma, which is there common both to the Lobes and Radicle, being by Vegetation augmented and prolonged into the Root, is here the Cortical Body, or that which is sometimes called the Barque.

The Contexture of this Cortical Body may be well illustrated by that of a Sponge, being a Body Porous, Dilative, and Pliable. Its Pores, as they are innumerable, so extream small. These Pores are not only susceptive of so much Moisture as to fill, but also to enlarge themselves, and so to dilate the Cortical Body wherein they are; which by the shriv’ling in thereof, by being expos’d to the Air, is also seen. In which dilatation many of its Parts becoming more lax and distant, and none of them suffering a solution of their continuity; ’tis a Body also sufficiently pliable; or, a most exquisitely fine-wrought Sponge.

The Extention of these Pores is much alike both by their length and breadth of the Root; which from the shrinking up of the Cortical Body, in a piece of a cut Root, by the same dimensions, is argu’d.

The proportions of this Cortical Body are various: If thin, ’tis called a Barque; & thought to serve to no other end, than what is usually ascrib’d to it as a Barque; which is a narrow conceit: If a Bulky Body in comparison with that within it, as in the young Roots of Cychory, Asparagus, &c. ’tis here, because the fairest, therefore taken for the prime Part; which, though, as to Medicinal use, it is; yet, as to the private use of the Plant, not so. The Colour hereof, though it be originally white, yet in the continued growth of the Root, divers Tinctures, as yellow in Dock, red in Bistort, are thereinto introduced.

Next within this Part stands the Lignous Body; the Original whereof, as of the two former, is from the Seed; or, the Seminal Roots of both the Lobes, being united in the Radicle, and with its Parenchyma co-extended, is here in the Root the Lignous Body.

The Contexture hereof is, in many of its parts, much more close than that of the Cortical; and their Pores very different: For whereas those of the Cortical are infinitely numerous, these of the Lignous are in comparison, nothing so. But these, although fewer, yet are they many of them more open, fair, and visible: as in a very thin Slice cut athwart the young Root of a Tree, and held up against the Light, is apparent: Yet not in all equally, in Coran-Tree, in Goosberry-Tree, &c. less; in Oak, Plums, and especially Damascens, more; in Elder, Vines, &c. more conspicuous. And as they are different in number and size, so also (whereon the numerousness of the Pores of the Cortical Body principally depends) in their shape. For whereas those of the Cortical Body are extended much alike both by the length and breadth of the Root; these of the Lignous are only by the length; which, especially in Vines and some other Roots, is evident. Of these Pores, ’tis also observable, that although in all places of the Root they are visible, yet most fair and open about the Fibrous Extremities of some Roots (and in many Roots higher) where there is no Pith. These Pores, as they shew in young Roots of Trees, see in Fig. 6, & 7.

This Lignous Body lieth with all its Parts, so far as they are visible, in a Circle or Ring; yet are there divers extream small Fibres thence shooting, usually mixed with the Cortical Body; and by the somewhat different colour of the said Cortical Body where they stand, may be noted these Fibres; the Cortical Body and Skin all together, properly make the Barque.

The proportion betwixt this Lignous Body and the Cortical, is various, as was said; yet in this, constant, sc. that in the fibrous, and smaller Parts of the Root, the Lignous Body is not only in compass, but in quantity the less; running like a slender Wyer or Nerve through the other surrounding it. They stand both together pyramidally, which is most common to Infant-Roots, but also to many other.

The next Part observable in the Root, is the Insertment. The existence hereof, so far as we can yet observe, is sometimes in the Radicle of the Seed it self; I cannot say alwayes. As to its substantial nature, we are more certain; that it is the same with that of the Parenchyma of the Radicle; being alwayes at least augmented, and so, in part, originated from the Cortical Body, and so, at second hand, from the said Parenchyma: For in dissecting a Root, we find, that the Cortical Body doth not only environ the Lignous, but is also wedg’d, and in many pieces inserted into it; and that the said inserted pieces, make not a meer Indenture, but transmit and shoot themselves quite through as far as the Pith; which in a thin Slice cut athwart the Root as so many lines drawn from the Circumference towards the Center, shew themselves. See Fig. 6, & 7.

The Pores of the Insertment are sometimes, at least, extended somewhat more by the breadth of the Root, as about the top of the Root of Borage may be seen; and are thus different from those of the Cortical Body, which are extended by the length and breadth much alike; and from those of the Lignous, being only by its length.

The number and size of these Insertions are various. In Hawthorn, and some others, and especially Willows, they are most extream small; in Cherries and Plums they are large; and in Damascens especially, very fairly apparent. In the Roots of small Plants they are generally more easily discoverable; which may lead to the observation of them in all.

These Insertions, although they are continuous through both the length and breadth of the Root; yet not so in all Parts, but by the several shootings of the Lignous Body are frequently intercepted. For of the Lignous Body it is (here best) observable, That its several shootings, betwixt which the Cortical is inserted, are not throughout the Root wholly distinct; but that all along being enarch’d, the Lignous Body, both in length and breadth, is thus disposed into Braces or Osculations. Betwixt these several shootings of the Lignous Body thus osculated, the Cortical shooting, and being also osculated answerably Brace for Brace, that which I call the Insertment is fram’d thereof.

These Osculations are so made, that the Pores of the Lignous Body, I think, notwithstanding, seldom run one into another; but, for the most part, still keep distinct; in the same manner as some of the Nerves, though they meet, and for some space are associated together, yet ’tis most probable that none of their Fibres are truly inosculated here, but only in the Plexures.

These Osculations of the Lignous Body, and so the interception of the Insertions of the Cortical, are not to be observ’d by the traverse cut of the Root, but by taking off the Barque, or the Cortical Body. In the Roots of Trees, they are generally obscure; but in Plants, often more distinctly apparent; and especially in a Turnep: the appearance whereof, the Cortical Body being stripp’d off, is as a piece of close-wrought Network, fill’d up with the Insertions of the said Cortical Body. See Fig. 8.

The next and last distinct Part of the Root is the Pith. The substantial nature thereof, is, as was said of the Insertment, the same likewise with that of the Parenchyma of the Seed. And according to the best observation we have yet made, ’tis sometimes existent in its Radicle; in which, the two main Branches of the Lobes both meeting, and being osculated together, are thus dispos’d into one round Trunk, and so environing part of the Parenchyma, make thereof a Pith; as in either the Radicle, or the young Root of the great Bean or Lupine, may, I think, be well seen.

But many times the Original hereof is immediately from the Cortical Body. For in dissection of divers Roots both of Trees and Plants, as of Barberry or Mallows, it is observable, that the Cortical Body and Pith are both of them participant of the same Colour; in the Barberry both of them tinged yellow, and in Mallows green. In cutting the smaller Parts of the Roots of many Plants, as of Borage, Mallows, Parsley, Columbine, &c. ’tis also evident, that the Lignous Body is not there in the least Concave, but standeth perfectly in the Center; and that the Insertions being gradually multiplied afterwards, the Pith at length, towards the thicker parts of the Root, shews and enlarges it self. Whence it appears, that in all such Roots, the Pith is not only of the same substantial nature, and by the Insertions doth communicate with the Cortical Body; and that it is also more or less augmented by it; which is true of the Pith of all Roots; but is moreover, by mediation of the said Insertions, wholly originated from it. The various appearances of the Insertions and Pith from the Fibrous Parts to the top of the Root, see in Fig. 9, 10, 11, 12, 13, 14. The Pores of the Lignous Body, entire in the said Fibrous Parts, are best seen when they have lain by a night dry, after cutting.

A farther evidence hereof are the Proportions betwixt the Cortical Body and Pith. For as about the inferiour Parts of the Root, where the Pith is small, the Cortical Body is proportionably great; so about the top, where the Pith is enlarged, the Cortical Body groweth proportionably less, sc. because by its Insertions, ’tis gradually bestowed into the Pith. Likewise the peculiar frame of some Roots, wherein besides the Pith, the Lignous Body being divided into a double Ring, there is also a thick Ring, of a white and soft substance, stands betwixt them; and is nothing else but the Insertions of the Cortical Body collected into the said Ring; but, towards the top of the Root, being inserted again, thus maketh a large and ample Pith; as in Fennel-Roots is seen.

The Pores of the Pith, as those of the Cortical Body, are extended both by the breadth and length of the Root, much alike; yet are they more or less of a greater size than those of the Cortical Body.

The Proportions of the Pith, are various; in Trees, but small; in Plants generally, very fair; in some making by far the greatest part of the Root; as in a Turnep: By reason of the wide circumference whereof, and so the finer Concoction and Assimilation of its Sap; that part which in most old Trunks is a dry and harsh Pith, here proves a tender pleasant meat. The parts of a Turnep in the travers cut see in Fig. 8.

In the Roots of very many Plants, as Turneps, Carrots, &c. the Lignous Body, besides its main utmost Ring, hath divers of its osculated Fibres dispersed throughout the Body of the Pith; sometimes all alike, and sometimes more especially in, or near, its Center; which Fibres, as they run towards the top of the Root, still declining the Center, at last collaterally strike into its Circumference; either all of them, or some few, keeping the Center still; of these principally the Lignous Body of the Trunk is often originated.

These Fibres, although they are so exceeding slender, yet in some Roots, as in that of Flower-de-liz, they are visibly concave, each of them, in their several Cavities also embosoming a very small Pith; the sight whereof, the Root being cut traverse, and laid in a Window for a day or two to dry, may without Glasses be obtained. And this is the general account of the Root; the declaration of the manner of its growth, with the use and service of its several parts, we shall next endeavour.

We say then, that the Radicle being impregnate, and shot into the Moulds, the contiguous moisture, by the Cortical Body, being a Body laxe and Spongy, is easily admitted: Yet not all indiscriminately, but that which is more adapt to pass through the surrounding Cuticle. Which transient Sap, though it thus becomes fine, yet is not simple; but a mixture of Particles, both in respect of those originally in the Root, and amongst themselves, somewhat heterogeneous. And being lodg’d in the Cortical Body moderately laxe, and of a Circular form; the effect will be an easie Fermentation. The Sap fermenting, a separation of Parts will follow; some whereof will be impacted to the Circumference of the Cortical Body, whence the Cuticle becomes a Skin; as we see in the growing of the Coats of Cheeses, of the Skin over divers Liquors, and the like. Whereupon the Sap passing into the Cortical Body, through this, as through a Manica Hippocratis, is still more finely filtred. With which Sap, the Cortical Body being dilated as far as its Tone, without a solution of Continuity will bear; and the supply of the Sap still renew’d; and the purest part, as most apt and ready, recedes, with its due Tinctures, from the said Cortical Body, to the Lignous. Which Lignous Body likewise super-inducing its own proper Tinctures into the said Sap; ’tis now to its highest preparation wrought up, and becomes (as they speak of that of an Animal) the Vegetative Ros or Cambium: the noblest part whereof is at last coagulated in, and assimilated to the like substance with the said Lignous Body. The remainder, though not united to it, yet tinctur’d therein, thus retreats, that is, by the continual appulse of the Sap, is in part carried off into the Cortical Body back again, the Sap whereof it now tinctures into good Aliment: So that whereas before the Cortical Body was only relaxed in its Parts, and so dilated; ’tis now increas’d in real quantity or number of parts, and so is truly nourish’d. And the Cortical Body being saturate with so much of this Vital Sap as serves it self; and the second Remainders discharged thence to the Skin; this also is nourish’d and augmented therewith. So that as in an Animal Body there is no instauration or growth of Parts made by the Bloud only, but the Nervous Liquor is also thereunto assistant; so is it here: the Sap prepared in the Cortical Body, is as the Arterious; and that part thereof prepared by the Lignous, is as the Nervous Liquor; which partly becoming Nutriment to it self, and partly being discharged back into the Cortical Body, and diffusing its Tincture through the Sap there, that to the said Cortical Body and Skin, becomes also true Nutriment, and so they all now grow.

In which growth, a proportion in length and breadth is requisite: which being rated by the benefit of the Plant, both for firm standing and sufficient Sap, must therefore principally be in length. And because it is thus requisite, therefore by the constitution of one of its Parts, sc. the Lignous Body, it is also made necessary. For the Pores hereof, in that they are all extended by its length, the Sap also according to the frame and site of the said Pores will principally move; and that way as its Sap moves, the same way will the generation of its Parts also proceed; sc. by its length. And the Lignous Body first (that is, by a priority causal) moving in length it self; the Cortical also moves therewith. For that which is nourish’d, is extended; but whatever is extended, is mov’d; that therefore which is nourish’d, is mov’d: The Lignous Body then being first nourish’d, ’tis likewise first mov’d, and so becomes and carries in it the Principle of all Vegetative motion in the Cortical; and so they both move in length.

Yet as the Lignous Body is the Principle of Motion in the Cortical; so the Cortical is the Moderator of that in the Lignous: As in Animal Motions, the Principle is from the Nerves; yet being once given to the Muscle or Limb, and that moving proportionably to its structure, the Nerves also are carried in the same motion with it. We suppose therefore, that as the principal motion of the Lignous Body is in length, so is its proper tendency also to ascend: But being much exceeded both in Compass and Quantity by the Cortical as in the smaller parts of the Root it is; it must needs therefore be over-born and governed by it; and so, though not lose its motion, yet make it that way wherein the Cortical Body may be more obedient to it; which will be by descent: Yet both of them being sufficiently pliable, they are thus capable, where the Soyl I may oppose a direct descent, there to divert any way where it is more penetrable, and so to descend obliquely. For the same reason it may also be, that though you set a Bean with the Radicle upward; yet the Radicle, as it shoots, declining also gradually, is thus arch’d in form of an Hook, and so at last descends. For every declination from a perpendicular Line, is a mixed motion betwixt Ascent and Descent; as that of the Radicle also is, and so seeming to be dependent upon the two contrary Tendencies of the Lignous and Cortical Bodies. What may be the cause of those Tendencies (being most probably external, and perhaps something of a Magnetisme) is besides my Task here to enquire.

Now although the Lignous Body, by the position and shape of its Pores, principally groweth in length; yet will it in some degree likewise in breadth: For it cannot be supposed that the purest Sap is all received into the said Pores; but that part thereof likewise, staying about its Superficial parts, is there tinctur’d and agglutinated to them. And because these Pores are prolonged by its length; therefore is it much more laxe and easily divisible that way; as in slitting a Stick, or cleaving of Timber, and in cutting and hewing them athwart is also seen. Whence it comes to pass, that in shooting from the Center towards the Circumference, and there finding more room, its said original Laxity doth easily in divers places now become greater, and at length in open Partments plainly visible. Betwixt which Partments, the cortical Body, being bound in on the one hand, by the surrounding Skin and Moulds, and pressed upon by the Lignous on the other, must needs insert it self, and so move contrary to it, from the Circumference towards the Center: where the said contrary motions continued as begun, they at last meet, unite, and either make or augment the Pith. And thus the Root is fram’d, and the Skin, the cortical and Lignous Bodies, so as is said, hereunto concurrent. We shall next shew the use of the two other Parts, sc. the Insertment and Pith; and first of the Pith.

One true use of the Pith is for the better Advancement of the Sap, whereof we shall speak in the next Chapter. The use we here observe is for the quicker and higher Fermentation of the Sap: For although the Fermentation made in the Cortical Body was well subservient to the first Vegetations, yet those more perfect ones in the Trunk which after follow, require a Body more adapted to it, and that is the Pith; which is so necessary, as not to be only common to, but considerably large in the Roots of most Plants; if not in their inferiour parts, yet at their tops. Where though either deriv’d or amplify’d from the Cortical Body, yet being by its Insertions only, we may therefore suppose, as those, so this, to be more finely constituted. And being also from its co-arctation, while inserted, now free; all its Pores, upon the supply of the Sap, will more or less be amplified: Upon which accounts, the Sap thereinto received, will be more pure, and its fermentation therein more active. And as the Pith is superiour to the Cortical Body by its Constitution, so by its Place. For as it thus stands central, it hath the Lignous Body surrounding it. Now as the Skin is the Fence of the Cortical Body, and that of the Lignous; so is the Lignous again a far more preheminent one unto the Pith; the Sap being here a brisk Liquor, tunn’d up as in a wooden Cask.

And as the Pith subserves the higher Fermentation of the Sap; so do the Insertions its purer Distribution; that separation which the parts of the Sap, by being fermented in the Pith, were dispos’d for; being, upon its entrance into the Insertions, now made: So that as the Skin is a Filtre to the Cortical Body, so are the Insertions a more preheminent one to the Lignous; and as they subserve the purer, so the freer and sufficient distribution of the Sap: For the Root enlarging, and so the Lignous Body growing thicker, although the Cortical and the Pith might supply Sap sufficient to the nutrition of its Parts next adjacent to them; yet those more inward, must needs be scanted of their Aliment; and so, if not quite starv’d, yet be uncapable of equal growth: Whereas the Lignous Body being through its whole breadth frequently disparted, and the Cortical Body inserted through it; the Sap by those Insertions, as the Blood by the disseminations of the Arteries, is freely and sufficiently convey’d to its intimate Parts, even those which from either the cortical Body or the Pith are most remote. Lastly, as the consequent hereof, they are thus assistant to the Latitudinal growth of the Root; as the Lignous Body to its growth in length; so these Insertions of the Cortical, to its better growth in breadth.

Having thus seen the solitary uses of the Several Parts of the Root, we shall lastly propound our Conjectures of that Design whereto they are all together concurrent, and that is the Circulation of the Sap: For the Sap moving through the cortical Body, towards the Pith, through the Insertions thereinto, obtains a pass: Which passage, the superiour Insertions will not favour; because the Pith standing in the same height with them, is there large, the fermenting and course of the Sap quick, and so its opposition strong. But through the inferiour it will much more easily enter; because there, through the smalness of the Pith, the opposition is little, and through the shortness of the Insertions, the way more open. So that though the Sap may meet with some opposition even here, yet here meeting with the least, here it will bestow it self (feeding the Lignous Body in its passage) into the Pith. Into which fresh Sap still entring, this, yet but crude, will subside: that first received and so become a Liquor higher wrought, will more easily mount upwards; and moving in the Pith, as in the Arteria magna, in equal altitude with the more superiour Insertions; the most volatile parts of all will still continue their direct ascent towards the Trunk. But those of a middle nature, and, as not apt to ascend, so being lighter than those beneath them, not to descend neither; they will tend from the Pith towards the Insertions in a motion betwixt both; through which Insertions (feeding the Lignous Body in its passage) it is, by the next subsequent Sap, discharged off into the cortical Body, as into the Vena cava, back again. Wherein, being still pursu’d by fresh Sap from the Center, and more occurring from the Circumference, towards the inferiour Insertions it thus descends; through which, together with part of the Sap afresh imbib’d from the Mould, it re-enters the Pith. From whence, into the Cortical Body, and from thence into the Pith, the cruder part thereof reciprocally is disburs’d; while the most Volatile, not needing the help of a Circulation, more directly ascendeth towards the Trunk.