( 472 ) 
vvouW happen, began to lofe of the intenfnefs of its colour^ which 
by degrees grew fainter and fainter, till at tlie end of three or four 
daies the liquor was grown very pa!e, and leFc me little doubt bm 
ibar, if I would have ftaidfome daies longer, it would have loft 
the remaining Eye of blew, and have lookc almoft like common 
water. But being unwilling to tarry fo long, I took out the 
ftopple, that the Air the Glafs might have accefs to that 
within ; and leaving the Vial in the fame place and pofturc,my ex- 
peflation was fomevvhat anfwer'd by finding, that within four or 
five minutes, if not lefs, the upper part of the liquor , that was 
contiguous to the Air, bad acquired a fine blew colour, which de- 
fcending deeper and deeper, before the end of the tenth minute 
had diffufed itfelf, but fomewhat weaken d, through the liquor, 
whofe colour was fuffer'd to deepen for a while longer ; fo that in 
lefs than a quarter of an hour from the firft unftopping of the Vial, 
-the liquor was grown to be throughout of a rich Ceruleous colour, 
which grew almoft too opacous within a few minutes longer: When 
carefully clofing the Vial again with the fame ftopple as before,we 
fet it afide in the fame place , where, the included Air being deni- 
ed all Commerce with the External, the liquor began again within 
two or three daies to lofe of its colour ; and, to be (horr, afforded 
me the opportunity of making a fecond Experiment, much like the 
former. And the like fuccefs 1 had, for^he main, inaTryal or 
two made iuanother Glafs with another portion of the fame Spi- 
rit of llrin, put upon the Filings of Copper 5 fo that the Expe- 
riment was, in all, made divers times, as well when I was not, as 
when I was alone : And particularly, once to be fure that the di- 
Air as fuch had not any great intereft in the Ph^emmemn ; I 
made the Tryal fuccefsfully about Nine a clock at night in th^ prc- 
fence of fo well-known a Witnefs as the Learned Secretary of the 
Royal Society. 
One Circumftance I forgot to take notice of, which was, that 
in moft of chefe Experiments I forbore to (hake the Glafs, left 
it fhouM be fufpefled, that the Agitation of the liquor might have 
raifedfome little fine powder that might have been fuppofed to 
have been precipitated out of thetinflure, and, being thus ming- 
led with the liquor again, reftore it to its former colour ^ but in 
• truth I did not perceive any fuch powder to be precipitated. And 
though, to obviate the objedtion, I forbore to fiiake the Vial ; 
yec 
