C H3 ] 
efpecially as to thofe Concretions genefated extra. Hdnttm m 
the Aomaclcand Guts : That thefefliould abound with Vola- 
tile Salt is ftrangCj I have tryed the Bezoar Stone ft id to be 
generated in the ftomacks of fbme Jnimalsj and could ob- 
tain no Volatile Salts from that6ubftance ; thougli it herein 
agree with this iyubftance, that it is eafily wrought on by 
many Acids. 
A Short Keview. 
We need not much doubt, though it be not mentioned, 
that thole cragged and large Stones^ were ejefted -per Anmn^ 
for the Oefofhagm could not poffibly pafs them. 
ThQ Stone in the Kjdney is often fo foft,that it anfwers the 
Cylindrical Figure of the Ureter ^ but thefe are much harder, 
and do not in any meafure comply with the Conftriclion of 
thQ Bowels. 
We may in fbme meafure queftion that principIe,or rather 
Hyfoihefis of Acidtim^ our Correfpondent trufts to, for the 
Combination ox Coagulation of the Humors in the Body, in or- 
der to this Petrifaction ; it being fuppofed not proved. 
We may alfo queftion whether the /ji;^ or j7r/?//^#^ Salt^ 
found in the Caput Mcrtuttm after Diftillation, were really 
pre-exiftent in that forme in the Blood,or other Humors^ and 
not rather a produft of the Fire. 
It may not be impertinent to inquire after fbme metaliick 
particlesjwhether they may not be an Ingredient in this pon- 
derous Stone, efpecially fince Dr, Lifier has f3und them in 
much lighter Concretions^ as thofe of tliQ Kjdneys are. For 
though we find them not in this unprepared ftone, yet after 
Reverberation or a ftrong Calcination, many bodks have de- 
teded an Iron Contexture. The Marchafite it felf, though 
very pregnant with Iron, Ihews it not, till it has been calci- 
ned : which fhall be done with fbme pf the remainder, after 
the Tryall by Diftillation. 
