(409 7) 
a general way deduced from the Commixture of thcife M!oe« 
ral Corpufclcs • fo the greatnefs of thofe virtues and the vat 
riety of thofe proprieties in particular may be afcribed to the 
peculiar nature of the impregnating liquors^to the diverficy of 
them, and CO the greaterand leffer proportions, wherein they 
are mixt with the petrefcent Juice» 
Hav^ing made this Conjeiiurc probable as to Tranfparem 
Gems, and withal occurred to fomcfpecIousObjetftionsjhe do* 
icends to make it our,that thofeArguments,which he hath pro^ 
duced to prove, that Diaphanous Gems may be endow'd with 
Virtues by the Mineral (ubftances they contain or are in part 
made up of^will hold more ftrongly as to Opacous ones : which 
he further confirms by four particular Arguments ; fetched 
fartly from the great fpecifick Gravity of divers Opacous and 
Medicinal ftones ; ^'iir/y from theficnefs of his Hypothefis to 
render a reafonof divers relating thereunto, fome 
of themfcarceat all, and others much lefs probably tobeac# 
counted for without it 5 partly from the Metallin fubftances 
to be manifeftly (eparated or obtained from the Stones he is 
treating of ; and partly from the Nature of the Bodies whereof 
Medicinal Stones feem to be compounded: In which laft it is 
peculiarly obferved by the Author, that the fubtlcty and pe- 
netrancy of fome Liquors,if duly con(idered,may evince it to 
be poflSble, that fuch Bodies fhould be petrified by them and 
with them^as may in part confift of Animal and Vegetable fub- 
ftances ;as in petrified Skulk^Bones^and pieces of Wood^ Be- 
fides, that not only there may be Bolus* s^StsXcdi Earths,and fuch 
like fofSIs that arc commonly known to be Medicinal, hard- 
ned into Stone by petrifying Agents ; but that alfo othet 
Earths, fubjcft to be petrified,may have Medicinal and fubtle 
particles of fuch a kind in them, as fcarce any body would 
expert: of which he alledges fome notable Inftances. But 
for them 5 and many other uncommon obfervables we muft 
refer the Curious fi.eader to the Book it lel£ 
Yyy y a II Johannis 
