some cases wherein I (who am somewhat backwards to admit Observations for
Universal) had the Curiosity to discover, that the Experiments would not
Uniformly succeed, and of these Exceptions, the chief that I now remember,
are reducible to the following three.

_EXPERIMENT XXVI._

And, (first) I thought fit to try the Operation of Acid Salts upon
Vegetable Substances, that are already and by their own Nature Red. And
accordingly I made Trial upon Syrrup of Clove-july-flowers, the clear
express'd Juice of the succulent Berries of _Spina Cervina_, or Buckthorn
(which I had long kept by me for the sake of its deep Colour) upon Red
Roses, Infusion of Brazil, and divers other Vegetable Substances, on some
of which crush'd (as is often mention'd) upon White Paper, (which is also
to be understood in most of these Experiments, if no Circumstance of them
argue otherwise) Spirit of Salt either made no considerable Change, or
alter'd the Colour but from a Darker to a Lighter Red. How it will succeed
in many other Vegetable Juices, and Infusions of the same Colour, I have at
present so few at hand, that I must leave you to find it out your self. But
as for the Operation of the other sorts of Salts upon these Red Substances,
I found it not very Uniform, some Red, or Reddish Infusions, as of Roses,
being turn'd thereby into a dirty Colour, but yet inclining to Green. Nor
was the Syrrup of Clove-july-flowers turn'd by the solution of Pot-ashes to
a much better, though somewhat a Greener, Colour. Another sort of Red
Infusions was by an _Alcaly_ not turn'd into a Green, but advanc'd into a
Crimson, as I shall have occasion to note ere long. But there were other
sorts, as particularly the lovely Colour'd juice of Buckthorn Berries, that
readily pass'd into a lovely Green.

_EXPERIMENT XXVII._