Chi] 
that by a violent Concuffion and agitation of their 
parts, which as foon part as the force is taken oflF. The 
various mixtures in a Torrent feem to make up one homo- 
geneous f?///^, but if fome part of this Fluid happen to 
iall into aPit, or ftagnate in a quiet place, we fliail find 
it clear it felf of Sand^ Mud and other differing parts. 
So great a difference there is betwixt the humors 
during their motion and agitation through Veins and 
Arteries, and when they are in the quiet Paffages of the 
IQdneys, or the more quiet ftate in the Bladder ^ , as there 
is betwixt a Torrent and a Well: the firftmay hurry a- 
long with it fuch grofs and ponderous parts, which eafi« 
ly fubfi.de in the other. 
That the Nature of this Concrete feems rather refer- 
rableto^of^e than to any other coniiftent or fluid part of 
the Body, I concluded by comparing Produfts 
which I only very briefly re:ate. 
Having cleared the of Marrow and Fat by boy- 
ling it in water, I diftilled it and obtained ^bout two 
drams and an half from an ounce of Bane of a volatile 
liquor impregnated with Salt , that fmelt very muGh 
like that I have mention'd, which was very differing from 
Spirit of Uir?;^^ ; and nearer that of Harts-horfi : I found 
the caput mortuum, as to weight,very confonant 5 and al- 
fo could extrad: no manner of fait from it. For which 
reafon j^yf;2^rj- make their Cupels of calcined Bones ^ they 
being forced to dulcify (v/hich they call wafliing out the 
falts of) other Jjhes before they can make Cupels of 
them. Laftof all it herein alfo agrees with the r^/^/z/^j^ 
Humanus^vxxXg^atly fo termed, that few Jcids will diffolve 
it, excepting thofethat are nitrous, nor do thefe w^ork 
on it very vigoroufly. 
Flerein they muft be aFow'd to differ in t\itn Jp^'cific 
Gravity, the Calculus not having fo clofe and compad a 
Texture as the Bones have. For BoneslhzYQ found t^ice 
as heavy as their Bulk of water. 
