as it was pour’d on it.  And if without Filtration you would gather together the flakes of this Vegetable Lake, you must pour a great Quantity of fair Water upon the Decoction after the affusion of the Alluminous Solution, and you shall find the Liquor to grow clearer, and the Lake to settle together at the bottom, or emerge to the top of the Water, though sometimes having not pour’d out a sufficient Quantity of fair Water, we have observ’d the Lake partly to subside, and partly to emerge, leaving all the middle of the Liquor clear.  But to make this Lake fit for use, it must by repeated affusions of fresh Water, be Dulcifi’d from the adhering Salts, as well as that separated by Filtration, and be spread and suffer’d to dry leisurely upon pieces of Cloth, with Brown Paper, or Chalk, or Bricks under them to imbibe the Moisture[25].

[Page 372] Annotation I.

Whereas it is presum’d that the Magistery of Vegetables obtain’d this way consists but of the more Soluble and Coloured parts of the Plants that afford it, I must take the liberty to Question the supposition.  And for my so doing, I shall give you this account.

According to the Notions (such as they were) that I had concerning Salts; Allom, though to sense a Homogeneous Body, ought not to be reckon’d among true Salts, but to be it self look’d upon as a kind of Magistery, in regard that as Native Vitriol (for such I have had) contains both a Saline substance and a Metall, whether Copper, or Iron, corroded by it, and associated with it; so Allom which may be of so near a kin to Vitriol, that in some places of England (as we are assur’d by good Authority the same stone will sometimes afford both) seems manifestly to contain a peculiar kind of Acid Spirit, generated in the Bowels of the Earth, and some kind of stony matter dissolv’d by it.  And though in making our ordinary Allom, the Workmen use the Ashes of a Sea Weed (vulgarly call’d Kelp) and Urine:  yet those that should know, inform us, that, here in England, there is besides the factitious Allom, Allom made by Nature Without the help of those Additaments.  Now (Pyrophilus) when I consider’d this composition of Allom, and that Alcalizate Salts are wont to Praecipitate what acid Salts have dissolv’d, I could not but be prone to suspect that the Curdled Matter, which is call’d the Magistery of Vegetables, may have in it no inconsiderable proportion of a stony substance Praecipitated out of the Allom by the Lixivium, wherein the Vegetable had been decocted, and to shew you, that there is no necessity, that all the curdl’d substance must belong to the Vegetable, I shall add, that I took a strong Solution of Allom, and having Filtred it, by pouring in a convenient Quantity of a strong Solution of Potashes, I presently, as I expected, turn’d the mixture into a kind of white Curds, which being put to Filtre, the Paper retain’d a stony Calx, copious enough, very White, and which seem’d to be of a Mineral Nature, both