a cause for the formation of stone, in many respects analogous to what is found in the strata of the earth, and which had come from the mineral region in a consolidated state, have, without due consideration, attributed to this cause all the appearances of petrifaction or mineral concretion.  It has been one of the objects of this work to show that this operation of incrustation, or petrifaction by means of solution, is altogether ineffectual for producing mineral concretions; and that, even were it capable of forming those mineral bodies, yet that, in the solid parts of this earth, formed by a deposit of travelled materials at the bottom of the sea, the conditions necessary to this incrustating process do not take place.

Those enlightened naturalists who have of late been employed in carefully examining the evidences of mineral operations, are often staggered in finding appearances inconsistent with the received doctrine of infiltration; they then have recourse to ingenious suppositions, in order to explain that enigma.  In giving examples of this kind.  I have in view both to represent the natural history these mineralists furnish us with, which is extremely interesting, and also to show the various shapes in which error will proceed, when ingenious men are obliged to reason without some necessary principle in their science.  We have just now had an example in Europe; I will next present the reader with one from Asia.

M. Patrin, in his Notice Mineralogique de la Daourie, (Journal de Physique, Mars 1791) gives us a very distinct account of what he met with in that region.  Describing the country of Doutchersk upon the river Argun, in Siberia, he proceeds thus: 

“Ces colines sont formees d’un hornstein gris qui paroit se convertir en pierre calcaire par l’action des meteores; car tout celui qu’on prend hors du contact de l’air donne les plus vives etincelles, et ne fait pas la moindre effervescence avec les acides, meme apres avoir ete calcine; et l’on observe celui qui est a decouvert, passer, par nuances insensibles, jusqu’a l’etat de pierre calcaire parfaite de couleur blanchatre.”

Here M. Patrin has persuaded himself, probably from an imperfect examination of the subject, that there takes place a mineral metamorphosis, which certainly is not found in any other part of the earth, and for which he does not find any particular cause.  The natural effect of the meteors, in other parts of the earth, is to dissolve the calcareous substance out of bodies exposed to those agents; and the gradation from the one of those two things to the other, which seems to be the data on which he had proceeded in forming his conclusion, is not sufficient to prove the metamorphosis, even were there not so strong a physical objection to it; for, it is by no means unusual for mineral bodies to graduate thus from one substance to another.  However that be, this is not the principal object of the example[42].