however, I suspected that the Tinging Particles did abound with such Salts, whose Texture, and the Colour springing from it, would probably be alter’d by peircing Acid Salts, which would in likelihood either make some Dissipation of their Parts, or Associate themselves to the like Bodies, and either way alter the Colour exhibited by them; whereupon Pouring into a small Vial full of Impregnated Water, a very little Spirit of Vinegar, I found that according to my Expectation, the Caeruleous Colour immediately vanish’d, but was deceiv’d in the Expectation I had, that the Golden Colour would do so too; for, which way soever I turned the Vial, either to or from the Light, I found the Liquor to appear always of a Yellowish Colour and no other:  Upon this I imagin’d that the Acid Salts of the Vinegar having been able to deprive the Liquor of its Caeruleous Colour, a Sulphureous Salt being of a contrary Nature, would be able to Mortifie the Saline Particles of Vinegar, and Destroy their Effects; And accordingly having plac’d my Self betwixt the Window, and the Vial, and into the Same Liquor dropt a few drops of Oyl of Tartar per Deliquium, (as Chymists call it) I observ’d with pleasure, that immediately upon the Diffusion of this Liquor, the Impregnated Water was restor’d to its former Caeruleous Colour; And this Liquor of Tartar being very Ponderous, and falling at first to the Bottom of the Vial, it was easie to observe that for a little while the Lower part of the Liquor appear’d deeply Caeruleous; whilst all the Upper part retain’d its former Yellowness, which it immediately lost as soon as either Agitation or Time had made a competent Diffusion of the Liquor of Tartar through the Body of the former Tincture; and this restored Liquor did, as it was Look’d upon against or from the Light, exhibit the Same Phaenomena as the Tincted Water did, before either of the Adventitious Liquors was pour’d into it.

Having made, Pyrophilus, divers Tryals upon this Nephritick Wood, we found mention made of it by the Industrious Jesuit Kircherus, who having received a Cup Turned of it from the Mexican Procurator of his Society, has probably receiv’d also from him the Information he gives us concerning that Exotick Plant, and therefore partly for that Reason, and partly because what he Writes concerning it, does not perfectly agree with what we have deliver’d, we shall not Scruple to acquaint you in his own Words, with as much of what he writes concerning our Wood, as is requisite to our present purpose. Hoc loco (says he)[17] neutiquam omittendum duximus quoddam ligni candidi Mexicani genus, quod Indigenae Coalle & Tlapazatli vocant, quod etsi experientia hucusque non nisi Caeruleo aquam colore tingere docuerit, nos tamen continua experientia invenimus id aquam in omne Colorum genus transformare, quod merito cuipiam Paradoxum videri posset; Ligni frutex grandis, ut aiunt, non raro in molem arboris excrescit, truncus illius eft