Page:Cyclopaedia, Chambers - Volume 2.djvu/942

 V E G T 285 ]

. The fame fucceds in a Sycamore, Walnut; t£c. tho the Tlux here is not fo copious. 'Phil. Tranfatl. N° 70.

There are Secrets whereby the Growth of Vegetables is furprizingly promoted. Mr. Boyle mentions a Virtuo r o, who entertain'd his Friends at the End of their Meal with a Sal- ted of Lettices, which he fow'd in their prefence, immedi- ately before they fat down to Table.

The Chymiils have furnifh'd us with Tome very extraor- dinary Vegetables ; as the Arbor "Diana, Arbor Mams, &c.

In effect, Gold, Silver, Iron, and Copper, being prepared in Aqua fortis, there rifes out of 'em a kind of Tree, which vegetates, or grows, to the naked Eye, and fpreads into Branches, Leaves, &c. the whole height of the Water ; till all the Matter is fpent therein. See Tree,

This Water the Chymiits call Bint-Water; the Secret whereof has been communicated by Rhodes Canall'es a Greek Chymift. ■" '

_ VEGETATION, the AB whereby Plants receive Nou- rifhment, and grow. See Plant, Vegetable, He.

Plants, we learn from the Microfcope, confill of different Parts, Veffels, t$c. analogous to thofe of Animals : And each kind of Veffel is fuppofed to be the Vehicle of a dif- ferent Humour, or Juice fecreted from the Mai's of Sap ; which is conlider'd as the Blood, or common Fund of them all. See Sap, and Blooii.

Dr. Grew affigns the Offices of the fcveral Veffels: Thofe placed on the inner Verge of the Bark, he calls Lympha- dltSs, and fuppofes 'cm deilin'd for the Conveyance of the moft aqueous or watery Liquor ; thefe, Mr. Bradley calls, the new forming Veffels, which are annually produced, and help to increafe the Bulk of the Tree.

Thofe in the middle of the Bark, Dr. Grew calls LaSi- ferotts, or Reftniferous Veffels ; their ufc, according to Bradley, is to return the fuperfluous Sap : Thefe Veffels, Grew obferves, are the principal Vifcera of Plants ; and adds, that as the Vifcera of Animals are but Veffels con- glomerated ; fo the Veffels of a Plant are Vifcera drawn out at length. See Viscera.

To the Nutrition of Plants, as well as Animals, it feems neceffary that there be a Concurrence of two fpecificaily dif- tinft Fluids ; and a learned Author maintains an Intermix- ture of two fuch Humors in every Part of a Tree, like that which we obferve in Linfey-wooliey : Every Part of Sap be- ing^ impregnated with other Tinctures, and continually fil- ter'd from Fibres of one kind to thofe of another. From this Mixture, many of the Phenomena of the Ripening, Odours, Colours, l$c. are accounted for.

V EG

The fecond Day; .the Secundine or Hull-, being broke thro' ; the Stem, or Top of the future Sttaw, appears b'ri the outhdc thereof, and grows upwards by degrees: In themeari time, the Seed- Leaf guarding the Robis, becomes turgid with its Vejlcula; and puts forth a white Down. And the Leaf being pull'd bare ; the future J"

"theory of Vegetation.

The Procefs of Nature in the Vegetation of Tlants, is very accurately deliver'd by the excellent Malftghi, to the Effect following.

The Egg (or Seed) of the Plant being excluded out of the Ovary, (call'd "Pod, or Husk) and requiring further fof- tering and brooding ; is committed to the Earth. See Seed, and Egg.

There, that kind Mother having receiv'd it into her Bo- fom, not only does the Office of Incubation, by her own warm Vapours and Exhalations, join'd with the Heat of the Sun ; but, by degrees, fupplies what the Seed requires for its further growth : as abounding every where with Ca- nals and Sinus's, wherein the Dew, and Rain-Water, im- pregnated with fertile Salts, glide, like the Chyle and Blood in the Arteries, (gc. of Animals.

This Moifture meeting with the new depofited Seed, is percolated, or ftrain'd thro' the Pores or Pipes of the outer Rind, or Huflc (correfponding to the Sectmdines of Fxtus's) on the infide whereof lie one or more, commonly two, thick Seminal Leaves, (anfwering to the Placenta in Women, and the Cotyledons in Brutes). See Secundine, Placenta,^.

Thefe Seed-Leaves confift of a great Number of little Vcficttla, or Bladders; with a Tube, correfponding to the Navel-ftring in Animals. See Umbilicus.

Into thefe Ve/icula is receiv'd the Moifture of the Earth, flrain'd thro' the Rind of the Seed ; which makes a flight Fermentation with the proper Juice before conrain'd therein.

This fermented Liquor is convey'd by the Umbilical Vef- fei to the Trunk of the little Plant ; and to the Gem or Bud, which is contiguous thereto : upon which, a Vegetation and increafe of the Parts fucceeds.

Such is the Procedure in the Vegetation of Plants ; which the illuftrious Author exemplifies in a Grain of Wheat ; as follows :

The full Day the Grain is Town, it grows a little turgid ; and the Secundine, or Hufk, gapes a little in feveral Places : and the Body of the Plant, being continued by the Umbi- lical Veffel to a conglobated Leaf, (which is call'd the Pulp or Fl?Jh of the Seed, and is what conftitutes the Flower) fwells ; by which means, not only the Gem, or Sprout, (which is to be the future Stem) opens, and waxes green ; but the Roots begin to bunch out ; whence the Placenta, or Seed Leaf, becoming loofe, gapes.

away, you fee the Roots of the Plant ud, Leaves; and reft of the Stalk, flill laying hid. Between the Roots, and the afcer.ding Stem, the Irunk of the Plant is knit by the Navel-knot to the! Flower-Leaf; which is very moift; tho it flill retains its white Colour, and its natural Taite.

The third Day, the Pulp of the conglobated of round Leaf, becomes turgid with the Juice which it has receiv'd from the Earth, iermenting with its own.

Thus the Plant increafes in bighefs, and its Bud of Stem! becoming taller, an .1 from whitifh, turns gieerii fh : Thelateral Roots alfo break foith grcenifh, and pyramidal from the gaping Sheaih, which adheres clofely to the Piant ; and the lower Root grows longer, and hairy, with many Fibre! fhooting out of the fame.

Indeed, thete are hairy Fibres hanging all along on all the Roots, except on their Tips ; and thefe Fibres are feen to. wind about the faline Particles of the Soil, little Lumps of Earth, t£c. like Ivy ; whence they grow curled. Above the lateral Roots, there now break out two other little ones.

The fourth Day, the Stem mounting upwards, makes a right Angle with the Seminal Leaf: The laft Roots put forth more; and the other three, growing larger, are clothed with more Hairs, which ftraitly embrace the Lumps of Earth ; and wh-jre they meet with any Vacuity, unite into a kind of Net-work. The Conglobate, or Flower- Leaf, is now fofter; andwhen bruis'd yields awhite fweetifh Juice, like Barley Cream. By stripping it off, the Root and Stem of the Plant are plainly feen, with the intermediate Navel-knot, whofe outer Part is folid, like a Bark, and the inner mote foft, and medullary.

The fifth Day, the Stalk ftill riling, puts forth a perma- nent or liable Leaf, which is green, and folded ; the Roots grow longer, and there appears a new Tumor of a future Root : The outer, or Sheath-Leaf is loofen'd ; and the: Seed-Leaf begins to fade.

The fixth Day, the Stable-Leaf being loofen'd, the Plant mounts upwards ; the Sheath-Leaf flill cleaving about it like a Bark. The Secd-Leaf is now feen finuous, or wrin- kled, and faded : and this being cut or freed from the Se- cundine, the Flefh, or Pericardium, is found of a different Texture ; the outer Part, whereby the outfide of the Seed or Grain is heaved up, being more folid ; but the iniide veficular, and fill'd with Humor : efpecially that Part next the Navel-knot. All the Leaves being pull'd oft", the Roots torn, and the Flower-Leaf rcmov'd, the Trunk appears 5 wherein, not far from the Roots, the Navel-knot bunches out, which is folid, and hard to cut : Above, there is the Mark of the Sheath-Leaf, which was pull'd off; and un- derneath, as in an Arm-pir, the Gem is often hid. The hind Part of the PLnt Ihews the breakings forth of the Roots, likewife the faded Placenta, &c.

After the eleventh Day, the Seed-Leaf, as yet flicking to the Plant, is crumpled, and almofl corrupted ; within it is hollow ; and about the Secundine, the mucous and white Subftance of the Seed being continu'd to the Navel-knot fotms a Cavity. Ail the Roots becoming longer, put forth new Branches out of their Sides: The Seed Leaf withers", and its Veficles are empty'd : The lnternodes, or Spaces be- tween the Knots, grow longer ; new Gems appear ; and the middle Root grows feverai Inches long.

After a Month, the Roots and Stalk being grown much longer, new Buds break out at the firft Knot, and little Tu- mors bunch out, which at length break into E.oots.

For other Ctrcumftances, fee. Generation, Sap, SeeDj R adicle, Plume, Per f en dicularity, Parallelism £S?g.

As to the Vegetable Matter, or the Food whereby Plants grow, there is fome doubt : The common Opinion, among Naturalifts, is, that Water is the great vegetable Food j which is confitm'd by an eafy Experiment.

A Sprig of Balm, Mint, or the like Plant, is fet in a Phial of pure Water, without any Mixture of Earth; yet the Sprig grows, puts forth Roots, Leaves, and Branches.

Agreeable to which, is another fam'd Experimenr of Van Helmont ; who drying 200 Pounds of Earth, and planting a. Willow which weigh'd five Pounds therein, he water'd it only with Rain, or dillili'd Water ; and to fecure it from; any other Earth, cover'd it with a perforated tin Cover : At five Years end, weighing the Tree, with ail the Leaves it had borne in that time, he found it to weigh 1S9 Pounds 5 Ounces ; yet the Earth was only diminifh'd two Ounces. See Water.

To afcertain this Point, Dr. Woodward has made feme very good Experiments; which, at the fame time, give light to many other Circumflances of Vegetation. His Experi- ments are moft of 'em with Sptigs of Mint, and fome other D d d <* Plants*