EXPERIMENT XXXIX
Take the dry'd Buds (or Bloſſoms) of the Pomegranate Tree, (which are commonly call'd in the Shops Balauſtiums) pull off the Reddiſh Leaves, and by a gentle Ebullition of them in fair Water, or by a competent Infuſion of them in like Water well heated, extract a faint Reddiſh Tincture, which if the Liquor be turbid, you may Clarifie it by Filtrating it Into this, if you pour a little good Spirit of Urine, or ſome other Spirit abounding in the like ſort of Volatile Salts, the Mixture will
preſently turn of a dark Greeniſh Colour, but if inſtead of the fore-mention'd Liquor, you drop into the ſimple Infuſion a little rectify'd Spirit of Sea-Salt, the Pale and almoſt Colourleſs Liquor will immediately not only grow more Tranſparent, but acquire a high Redneſs, like that of Rich Claret Wine, which ſo ſuddenly acquir'd Colour, may as quickly be Deſtroy'd and turn'd into a dirty Blewiſh Green, by the affuſion of a competent quantity of the above-mention'd Spirit of Urine.
Annotation.
This Experiment may bring ſome Light to, and receive ſome from a couple of other Experiments, that I remember I have met with in the ingenious Gaſſendus's Animadverſions upon Epicurus's Philoſophy, whilſt I was turning over the Leaves of thoſe Learned Commentaries; (my Eyes being too weak to let me read ſuch Voluminous Books quite thorough) And I the leſs ſcruple (notwithſtanding my contrary Cuſtom in this Treatiſe) to ſet down theſe Experiments of another, becauſe I ſhall a little improve the latter of them, and becauſe by comparing there with that which I have laſt recited, we may be aſſiſted to Conjecture
upon what account it is, that Oyl of Vitriol heightens the Tincture of Red-roſe Leaves, ſince Spirit of Salt, which is a highly Acid Menſtruum, but otherwiſe differing enough from Oyl of Vitriol, does the ſame thing. Our Authors Experiments then, as we made them, are theſe; We took about a Glaſs-full of luke-warm Water, and in it immerg'd a quantity of the Leaves of Senna, and preſently upon the Immerſion there did not appear any Redneſs in the Water, but dropping into it a little Oyl of Tartar, the Liquor ſoon diſcover'd a Redneſs to the watchfull Eye, whereas by a little of that Acid Liquor of Vitriol, which is like the former, undeſervedly called Oyl, ſuch a Colour would not be extracted from the infuſed Senna. On the other ſide we took ſome Red-roſe Leaves dry'd, and having ſhaken them into a Glaſs of fair Water, they imparted to it no Redneſs, but upon the affuſion of a little Oyl of Vitriol the Water was immediately turn'd Red, which it would not have been, if inſtead of Oyl of Vitriol, we had imployed Oyl of Tartar to produce that Colour: That theſe were Gaſſendus his Experiments, I partly remember, and was aſſur'd by a Friend, who lately Tranſcribed them out of Gaſſendus his Book, which I
therefore add, becauſe I have not now that Book at hand. And the deſign of Gaſſendus in theſe Experiments our Friend affirms to be, to prove, that of things not Red a Redneſs may be made only by Mixture, and the Varied poſition of parts, wherein the Doctrine of that Subtil Philoſopher doth not a little Authorize, what we have formerly delivered concerning the Emergency and Change of Colours. But the inſtances, that we have out of him ſet down, ſeem not to be the moſt Eminent, that may be produced of this truth: For our next Experiment will ſhew the production of ſeveral Colours out of Liquors, which have not any of them any ſuch Colour, nor indeed any diſcernable one at all; and whereas though our Author tells us, that there was no Redneſs either in the Water, or the Leaves of Senna, or the Oyl of Tartar; And though it be true, that the Predominant Colour of the Leaves of Senna be another than Red, yet we have try'd, that by ſteeping that Plant a Night even in Cold water, it would afford a very deep Yellow or Reddiſh Tincture without the help of the Oyl of Tartar, which ſeems to do little more than aſſiſt the Water to extract more nimbly a plenty of that Red Tincture, wherewith the Leaves of Senna
do of themſelves abound, and having taken off the Tincture of Senna, made only with fair Water, before it grew to be Reddiſh, and Decanted it from the Leaves, we could not perceive, that by dropping ſome Oyl of Tartar into it, that Colour was conſiderable, though it were a little heightned into a Redneſs; which might have been expected, if the particles of the Oyl did eminently Co-operate, otherwiſe than we have expreſſed, to the production of this Redneſs.
And as for the Experiment with Red-roſe Leaves, the ſame thing may be alleged, for we found that ſuch Leaves by bare Infuſion for a Night and Day in fair Water, did afford us a Tincture bordering at leaſt upon Redneſs, and that Colour being conſpicuous in the Leaves themſelves, would not by ſome ſeem ſo much to be produc'd as to be extracted by the affuſion of Oyl of Vitriol. And the Experiment try'd with the dry'd Leaves of Damask-roſes ſucceeded but imperfectly, but that is indeed obſervable to our Authors purpoſe, that Oyl of Tartar will not perform in this Experiment what Oyl of Vitriol doth; but becauſe this laſt named Liquor is not ſo eaſily to be had, give me leave to Advertiſe you, that the Experiment will ſucceed,
if inſtead of it you imploy Aqua-fortis. And though ſome Trials of our own formerly made, and others eaſily deducible from what we have already deliver'd, about the different Families and Operations of Salt, might enable us to preſent you an Experiment upon Red-roſe Leaves, more accommodated to our Authors purpoſe, than that which he hath given us; yet our Reverence to ſo Candid a Philoſopher, invites us rather to improve his Experiment, than ſubſtitute another in its place. Take therefore of the Tincture of Red-roſe Leaves, (for with Damask-roſe Leaves the Experiment ſucceedeth not well) made as before hath been taught with a little Oyl of Vitriol, and a good quantity of fair Water, pour off this Liquor into a clear Vial, half fill'd with Limpid water; till the Water held againſt the Light have acquir'd a competent Redneſs, without loſing its Tranſparency, into this Tincture drop leiſurely a little good Spirit of Urine, and ſhaking the Vial, which you muſt ſtill hold againſt the Light, you ſhall ſee the Red Liquor immediately turn'd into a fine Greeniſh Blew, which Colour was not to be found in any of the Bodies, upon whoſe Mixture it emerg'd, and this Change is the more obſervable, becauſe in many Bodies