La calcedoine y est de meme, ou bien en mamelons, ou bien en
stalactites, lorsqu'elle a de la place pour s'y deposer.
"Un phenomene encore plus curieux que cela est cette belle pyrite
sulphureuse jaune, comme de l'or, qui est quelquefois parsemee par tout
la substance de petrifications agathisees, et qui apparemment y fut
deposee apres la dite metamorphose a la faveur des petits pores, qui y
etoient restes ouverts."
I would beg that mineralists, who use such language as this, would
consider if it contains a distinct idea of the operation which they
would thereby describe, or if it does not contain either a contradiction
or an inconceivable proposition. It supposes a calcareous body to be
metamorphosed, somehow by means of the mountain acid, into a siliceous
body. But, finding many bodies of pyrites contained within that solid
flint, it is said, that, when the calcareous body was flintified, there
were left in it cavities which were afterwards filled with pyrites. Let
us reflect a moment upon this doctrine. These cavities were first open
to the outside of the flinty body; but now the pyrites with which they
had been filled is insulated in the solid flint.
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