interspers'd Particles of the red Liquor had not a little Allay'd the
Purity, though not blemish'd the Beauty of the Colour. And to shew you,
_Pyrophilus_, that these Effects do not flow from the Oyl of Vitriol, as it
is such, but as it is a strongly Acid _Menstruum_, that has the property
both to Præcipitate Lead, as well as some other Concretes out of Spirit of
Vinegar, and to heighten the Colour of Red Rose-leaves, I add, that I have
done the same thing, though perhaps not quite so well with Spirit of Salt,
and that I could not do it with _Aqua-fortis_, because though that potent
_Menstruum_ does as well as the others heighthen the Redness of Roses, yet
it would not like them Precipitate Lead out of Spirit of Vinegar, but would
rather have dissolv'd it, if it had not found it dissolv'd already.

And as by this way we have produc'd a Red Liquor, and a White Precipitate
out of a Dirty Green magistery of Rose-leaves, so by the same Method, you
may produce a fair Yellow, and sometimes a Red Liquor, and the like
Precipitate, out of an Infusion of a curious Purple Colour. For you may
call to mind, that in the Annotation upon the 39th. Experiment I intimated
to you, that I had with a few drops of an Alcaly turn'd the Infusion of
Logg-wood into a lovely Purple. Now if instead of this Alcaly I substituted
a very Strong and well Filtrated Solution of _Minium_, made with Spirit of
Vinegar, and put about half as much of this Liquor as there was of the
Infusion of Logg-wood, (that the mixture might afford a pretty deal of
Precipitate,) the affusion of a convenient proportion of Spirit of Salt,
would (if the Liquors were well and nimbly stirr'd together) presently
strike down a Precipitate like that formerly mention'd, and turn the Liquor
that swam above it, for the most part into a lovely Yellow.

But for the advancing of this Experiment a little further, I consider'd,
that in case I first turn'd a spoonfull of the infusion of Logg-wood
Purple, by a convenient proportion of the Solution of _Minium_, the