( M ) 
!t is hard to give a Mechanical Reafon of this fo fS- 
cret and hidden a matter ; though it is really as certain 
it muft depend upon feme Phyfical Caufe; and to offer 
at feme reafonable Conjefture, the Author examines 
whether thefe Bones were thus united while the Fcstus 
was in the Mother's Womb while the Perfcn was living, 
or after its Death in the Ground : Tliough the two lall 
Opinions appear moft likely to feme Perlons, yet he al- 
lows neither of them ; for as to the Earth, it is eicher 
pure and Elementary, ot impregnated with fome Prin- 
ciple capable to produce the Effedt. Pure Earth being 
made up cnly of fryable, porous, irregular Particles, 
can but fuck up the fupeificial Mclfture of the Liga- 
ments of this Trunk, otherwife by Evaporation in the 
Sun Ligaments and Cartilages wcuid become Bony; 
and the Earth is never fo ftiptique as to procure fo inti- 
mate an Union. If you will fay, the Earth was im- 
pregnated with fome Principle, it mufl be either Water, 
Sulphur, or Salt ; neither of which feem proper to ce- 
ment Bones : All know that Water and Sulphur are fo 
far from hardening Ligaments, that they rather fofteo 
and relax by their flipp^ry and fluid Particles. Nor does 
he think Alkalis or Acids are capable to turn to Bone. 
Firfl:, Alkali's being briftly, ftiff, and inflexible, are pro- 
perer to feparate than unite,- as is feen by putting a 
piece of a Ligament into any Alkaline Salt. And Se- 
condly, Acids are moft proper to break the Texture , 
and divide even the hardeft Bodies, and upon Experi- 
ment Cartilages are diflblved in them ; befides, could 
this Effeft have been produced in the Earth, why wns 
not the whole Body turned to Bone? Our Author gives 
feveral other Reafons for his reje£ling this Opinion, 
touchingupon the manner of Petrifadion, which he fays, 
islDy the littleAcid A^^/^i, which being in a fluid date, 
infinuate themfelves into and flop up the Pores of the 
petrified Bodies, rendering them more compadt. He 
attempts 
