es and Operations of Salt, might
enable us to present you an Experiment upon Red-rose Leaves, more
accommodated to our Authors purpose, than that which he hath given us; yet
our Reverence to so Candid a Philosopher, invites us rather to improve his
Experiment, than substitute another in its place. Take therefore of the
Tincture of Red-rose Leaves, (for with Damask-rose Leaves the Experiment
succeedeth not well) made as before hath been taught with a little Oyl of
Vitriol, and a good quantity of fair Water, pour off this Liquor into a
clear Vial, half fill'd with Limpid water; till the Water held against the
Light have acquir'd a competent Redness, without losing its Transparency,
into this Tincture drop leisurely a little good Spirit of Urine, and
shaking the Vial, which you must still hold against the Light, you shall
see the Red Liquor immediately turn'd into a fine Greenish Blew, which
Colour was not to be found in any of the Bodies, upon whose Mixture it
emerg'd, and this Change is the more observable, because in many Bodies the
Degenerating of Blew into Red is usual enough, but the turning of Red into
Blew is very unfrequent. If at every drop of Spirit of Urine you shake the
Vial containing the Red Tincture, you may delightfully observe a pretty
variety of Colours in the passage of that Tincture from a Red to a Blew,
and sometimes we have this way hit upon such a Liquor, as being look't upon
against and from the Light, did seem faintly to emulate the above-mention'd
Tincture of _Lignum Nephriticum_. And if you make the Tincture of Red-roses
very high, and without Diluting it with fair Water, pour on the Spirit of
Urine, you may have a Blew so deep, as to make the Liquor Opacous, but
being dropt upon White Paper the Colour will soon disclose it self. Also
having made the Red, and consequently the Blew Tincture very Transparent,
and suffer'd it to rest in a small open Vial for a Day or two, we found
according to our Conjecture, that not only the Blew but the Red Colour also
was Vanish'd; the clear Liquor being of a bright Amber Colour, at the
bottom of which subsided a Light, but Copious feculency of almost the same
Colour, which seems to be nothing but the Tincted parts of the Rose Leaves
drawn out by the Acid Spirits of the Oyl of Vitriol, and Precipitated by
the Volatile Salt of the Spirit of Urine, which makes it the more probable,
that the Redness drawn by the Oyl of Vitriol, was at least as well an
extraction of t