Gabriel Plattes, A Discovery of Subterranean Treasure (London: Parker, 1679), 23.

[at the end of a section about prospecting globally for colors):

And whereas Barks, Woods, and Roots are of a dry composition, and will not firment of themselves with water like green Herbs, or vegetalbes, therefore they must be well ground, or thinn shaven and there must be added in stead of Water, Juice of Grapes, Pears, Apples, or Wort made of Malt, or other grain , into which the Wood Bark, or Roots must be put: let them ferment together, and afterwards be turned into Vinegar; then the clear Vinegar must be extracted: the residue of the tincture must be extracted with fresh water, and both of them must be breathed away in the Sun, as before, and so brought into his perfect tincture.

By this which hath been declared in this Chapter, it may appear to every one  having an inquisive disposition, what is the true naturall cause why some colours are fixed, and will not stain with vinegar, urine, nor yet fade with the Air; which hath in it a certon acetosity, or sharp airy salt of the nature of Vinegar, which those tinctures draw to them, which have not their Appetites fully satisfied before with such spirituall or airy salts; and this is further manifest for that all such tinctures which are most firm and fixed, and are not subject to staining or fading, being tasted upon the tongue, may be felt somewhat sharpish or sowrish.

And the cause of this appetitive and attractive vertue in colours is no other but the very same which is betwixt the Load-stone and Iron: for take the Load-stone, and burn it till all his blew vapour be exhaled, and then he will draw no more Iron: thereby shewing plainly, that it was the airy salt, tincted with the venerall, or vegetable greenness, which the Iron thirsted after, to satisfy his thirsty and dry nature and constitution, which he got by his calcination and fusion.

And the like attraction may be discerned by the intellectual eyes, in any thing that is strongly burnt, so that all his Spirits are exhaled: as Lime will draw the airy substance to him, and thereby quench himself: Also Tartar burned, and laid in the Air, will draw the sharper part of the air to it, and thereby dissolve it self: and in summ all corporeall substances, the more they have lost their spirituall parts by naturall, or artificiall operation, the stronger is their Attractive vertue.

Now in stead of filling the Readers head with Proclamations, I will conclude my Book with giving ease to his memory,  by prescribing what necessaries he is to provide for the accomplishing of his severall designs, in his Voyages or Plantations, whither his occasion shal draw him. . . .