C SCO ) 
long to be preferred, but do grow turbid, (bme pale, 
and coloarkfs, and leave their Mendruums^ and preci- 
pitate to the bottom, and are noteafily if ever recover'd. 
But in our Experiment we have fome things very un- 
common, a deeply tingd Liquor grows pale andcolour- 
lefs in a few days, without any admilTion of Air or any 
other Ingredient to difturb it, or to caufeany difcern- 
able precipitation cr feparation. Yet when I confider 
that two Grains of Copper will give a deep Colour to 
three Ounces of Urinous Spirits, we need not expect any 
great quantity ihould bedifcharg'd out of the Liquor to 
be very confpicuous at the bottom, which does better 
folve it than a bare change of Texture can do; namely, 
to allow it to fubfide to the bottrm of the Glafs, tho' it 
be fcarce perceptible by reafen of the Fiieings that may 
conceal it. But a yet greater difficulty emerges to ac- 
count for, which is, That fince our Menftruum, (that is, 
cur Sprit J is diverted of its Venereal Particles, uhich 
gave the Tin&ure, and is become as clear as Rock-water, 
and being (eparated from its Metalline Fiieings, does yet 
upon the approach of the Air immediately afford a very 
Blue Tincture, This indeed plainly (hews, that there 
mud be conceal'd in the Pores of the Liquor, fuch Parti- 
cles as are of a Cupreous Nature. But how may this 
come to pafs ? To which I anfwer, I cannot be fo vain 
to chink, that the Air gives the matter of the Colour to 
the Spirit, but that it conveys into it fuch Particles as do 
(linaukte and give morion to the Menftruwrn, and inable 
i: to cuToive thole Particles thoroughly, that for want 
c: ropreAir hid no: b:en fully broken in pieces. 
In the next place, I difcover two very differing forts 
of Ma::er that cur Urinous Menfiruum a!ts upon in this 
Experiment. One I call a Sulphureous Matter, which 
g *es*he Bloe Colour, and does let it fall again; and a- 
r*oi \et which deferves the name of Saline; but tho J it 
be taken up into pur tinging Spirit, does yet nctwith- 
flandirg 
