C 4095 ) 
|ound and a Httle flatted j of am t>lfre ^okmr ^ mark^ 
ed with red (pecks ^ like coagulated bloodf and &i po^ 
lirtied and flbioiag,that it refleded Images> It was Wrapped 
up in a membrane full of fat^^and faftned on both ends to the 
back boaej over againft the Kidneys* Though this Horfe 
had been dead twelve hours before it was opened ; yet was it 
ftill v^y warm^ and kept that warmth above fix hours after 
ic was opened. This ftone is kept among the Rarities ofSig- 
nor Bartolmi^ an Itahan Riding-maften 
An Accmpt of [ome Boo^s. 
I. An ESSJr about the OrigineandVertues of GEMS ; hy th 
Honourabh Robert Boyl Efquire, Fellow of the R, Society* 
Friuted at London^ i6j2^ tn§^. 
TH E defign of the Noble Author of this excellent Trea* 
tife being,to propofe and hiftorically to illuftrate therein 
fome conjedtures of his about the Confiftence of the Matter of 
Precious Stones, and the Subjects wherein their chief vertues 
refidej he comprifes thefubftance of all in thefe ^ot partieu- 
lars; F/r/?,That many of thefe Geriis,and the Medical Stones^ 
eicher were oncej/^^^^Bodies^as theTranfparent ones,orin part 
made up of fuch fubftanccs as were once iSuid. Secondly^Th^t 
many of the real virtues of fuch Stones may be probably deri- 
ved from the mixture ofMetalline and other mineral fubftanccs, 
which are ufually (though unfufpededty) incorporated With 
themjand that thQgreatnefs of the Variety and Efficacy of thofe 
. virtues may be attributed to fome happy concurrent circum- 
ftances of that commixture. 
The /r/?of thefe Heads relateth properly to ^t Oripne of 
Gems : %hcfe€ond,pztt\y to thatgand partly to thc^nds and de- 
greej of their virtues. 
To countemnce the former, the Author alledges for his ^rfi 
, Argument feveral^onfiderationSsfakeufirft from the Diapha^ 
.^neity of Gems^^ fecondlyj their external gguratiod § thirdly^ 
their internal texture j fourthly, their Colours that feem to be 
^^^as^yentitious and imparted by fome coloured Mineral Juice^dr ' 
^iocaetinging Mineral exhalation^ v^hilft the Ston^%as either 
Yy yy m 
