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Show ‘The Colours Lea. V. a “2. § Firft, Ofthofe feveral Colours, which appear in Plants in their HY /tate. Spar ey, As they appear upon the Infifion of Plants into reral Sorts of Liquors. reeeTbindly As upon the Mixture of thofe Infufions, or of any one of themwith fome other Liquor, or other Body. 5. g. As they appear in the Plants themfclves, it may be obferved inthe firft place, That thereisafar lefs variety in the Colours of Roots, than of the other Parts: the Parenchyma being, within the Skin, ufually White, fometimes Yeow, rarely Red. The Canje hereof being, for that they are kept, by the Earth, from a free and open Aer 3 which concurreth with the Juyces of the feveral Parts, to the Produéfion of their feveral Colours.” And therefore the upper parts of Roots, when they happento ftand naked above the Ground, are often deyed with {everal Colours : fo the tops of sorrel Roots will turn Red,thofe of Mullen, Turneps and Radifhes, will turn purple, and many others green. Whereas thofe parts of the fame Roots which lie more under Ground, ; only White. ee AsRows are moft commonlyWhites fo the Leaves, Green, Which Colour is fo proper to them, that many Leaves, as thofe of Sage, the young sprouts of St. Fobus-wert, and others, which are Redifh when in the Bud 5 upon their full Growth, acquirea perfect Green. 7. §. The canfe ofthis Colour, is the ation of the Aer, both from within, and from without the Plant, upon the Fuyces thereof, where- , by it ftrikes them into that Colour. 8. §. Bythe Aer from without, I mean that which furrounds the Body of the Plant: which is the Caufe of its Greenefs, not meerly as it is contiguous to it, but as it penetrates through the Pores of the Skin, thereinto; and fo mixing with the Fuyces thereof, plainly deys : : or ftrikes them into a Greez. 9. §. Bythe Aer from within, I mean, that which entring, together with the Aliment, at the Root, thence afcends by the Aer-Veffels, into the Truk and Leaves, and is there transfufed into all the feveral Fuyces,therebylikewife concurring to their Verdure. Whence it is, that the Parts of Plants which lie under Water, are Green,as well as thofe which ftand aboveit 5 becaufe, though the ambient Aer, conteined in the Water be butlittle, yet the want of it is compenfated, by that whichafcends from the Root. to. g. And therefore itis obfervable, that the stalks of MarfhMallow, and fome other Plants, being cut tran{verfly, though the Parenchyma in the Barque be white, yet the Sap-Vefféls which lie within that Parenchyma, are as Green as the Skin it felf; cil. becaufe they {tandclofe to the Aer-Veffels. The Parenchyma, 1 fay, whichis intercepted from the Aer, without, by the shiz; and from the Aer within, bythe sap-Vefels, is white: but the Shiv, which is expofed to the Aer without, and the Sap-Vefvels which are next neighbours to that within, are both equally Gree. So likewife if a Carrot be plucked up, and {uffered to lie fometime in the open Aer; that part which ftandeth in andnear the Centre, among{t the Aer-Veffels, will become Green as well as the shin , all theother Parts continuing of a Redifh Yellow, as before. The Aer therefore, both from without, and from within the Plant, together with the Fuyces of the Plant, are all the concurrent Canfes of : Verdure Lise Led. V. of Plants. 1t. g. BUT how doth the Aer concur to the Greenefs of Plants 2 I anfwer 5 Notas it is meerly either cold or dry, or moift, nor yet quatenus Aer 5 but as itis a mixed, and particularly, a Saline Body: that is, as there is a confiderable quantity of Suline Parts mixed with thofe which are properly dereal. It being plain from manifold Experience ; That the feveral kinds ofSalts, are the grand Agents in the Variation of Colours. So that, to {peak ftridtly, although Swlphur be indeed the Female, or Materia fabftrata, ofall Colours; yet Salt is the Mule or Prime Agent, by which the Sulphur is determined to the Produdion of one Colour, and not of another. 2, §. If then it be the Aer mixed with the Fuyces of a Plant, and the Salt ofthe Aer, that makes it Geen 5 It may further be asked, what kind of Salt? But this is more hard to judge of Yet it eemeth,that it is not an Acid, but a Subalkaline Salt; or at leaft fome Salt which is different from fimple Acid, and hath an Affinity with Alkalies. 13. g. One reafon why I fo judge, is, Becaufe that although all Plants yield an Alkaly, or other Salt different from an Acid, and fome in good quantity; yet in moft Plants, the Predominant Principle is an Acid. So that the Supply of an Acid Principle from the Aer, for the Produétion of a Green Colour, as it would be fuperfluous 3 So alfo ineffectual : a different Principle being requifite to the ftriking ofthis, together with the Sulphur, into a Green Colour. 14. §. I fuppofe therefore, That not only Greew, but all the Co- lours of Plants, are a kind of Precipitate, refulting from the concur- rence of the Saline Parts of the Aer, with the Saline and sulphurious Parts of the Plant; and that the Subalkaline, or other like Saline Part of the Aer, is concurrent with the Acid and Sulphurious Parts of Plants, for the Produttion of their Verdure that is, as they ftrike altogether into a Green Precipitate. Which alfo feemeth to be confirmed by divers Experiments hereafter mentioned, 15. § THE Colours of Flowers are various ; differing therein not only from the Leaf, but one from another. Yet all feem to depend uponthe general Canjes aforefaid. And therefore the Colours of Flowers, as well as of Leaves, to refult not folely from the Contents of the Plant, but from the concurrence likewife of the ambient Aer. Hence it is, that as they gradually open, and are expofed to the Aer,theyftill either acquire, or change their Colour: no Flower having its proper Colour in the Bud, (though it be then perfedtly formed) but only whenit is expanded. So the Purple Flower of Stock-Fuly Flowers, while they are inthe Bud, are white, or pale. So Butchelors Buttons, Blew Bot- tle, Poppy, Red Daifies, and many others, though of divers Colonrs when blown, yet are all white in the Bud. And many Flowers do thus change their Colours thrice fucceflively; asthe youngeft Buds of Ladys-Lookinglafs, Euglofs and the like, are all white, the larger Buds are purple or murrey, and the open Flowers, blew: according as they comeftill neerer, and are longer expofed, to the Aer. 16. ¢. But if the Colour of the Flower dependeth on the amsbient Aer 5 it may be asked: How it comes to pafs then, that this Colouris various, and not one, and that one, a Greer? that isto fay that all Flowers are not Green, as well as the Leaves ? In anfwer to this Three things are to be premifed. |
