How is a petrified body formed? Science answers, that it is formed by the gradual infiltration of silicious earth, pyrites of iron, carbonate or sulphate of lime, into the pores of the body, taking the place of the decaying parts, and substituting a new and original substance to take the place and form of the body petrified. These substances are always conveyed to their place of destination, and then applied to accomplish their purpose by the operation of water. The petrified substance may have none of the material composing the original figure, and the nature of the body formed either assimilates to the material around it, or is determined by that of which it is composed. So also all of the substances forming petrifaction may be found together in the same subject, or they may accomplish their work separately. Silicious earth goes largely to form flint quartz and the various kinds of sandstone carbonate of lime, of limestone, and so of the other materials mentioned forming their peculiar kinds of stone. I have heard one statue-theorist trying to prove that the decayed portion of one of the legs showed the presence of flint, and therefore he argued it could not be a petrifaction. Not so. It probably would prove, if true, that the figure was not a statue, for pieces of flint are not found in such material, unless it be a petrifaction, in which case silicious earth would account for it. Now it is safe to say that there is no substance that enters into the composition of stone that does not enter into the formation of a petrifaction. Now, these materials are, in cases of petrifaction, brought to the spot and deposited by action of the water--precisely such an operation as forms strata of rock; should it not produce the same effect in the appearance of successive layers or strata in the subject of petrifaction? With reference to the other objection to the theory of petrifaction, viz:--that the members of the body are conjoined and not detached--it is sufficient to say, from the very nature of the operation of petrifaction, portions of the body lying in contact would necessarily be conjoined and filled up. The wasting portions of the body are silently but surely supplied by nature, and as the transformation progresses, nature causes her deposit to adhere to its proximate kindred matter, and forms thus a solid and adhering body.