Theory of the Earth

in those masses may be formed. In this case, therefore, where the means are not naturally in the supposition, a philosopher, who is to explain the phænomenon by the natural operation of water in this situation, must not have recourse to another agent, still more powerful, to assist his supposition, which cannot be admitted.

THUS, it will appear, that, to consolidate strata formed at the bottom of the sea, in the manner now considered, operations are required unnatural to this place; consequently , not to be supposed in order to support a hypothesis.

BUT now, instead of enquiring how far water may be supposed instrumental in the consolidation of the strata which were originally of loose texture, we are to consider how far there may be appearances in those consolidated bodies, by which it might be concluded, whether or not the present state of their consolidation has been actually brought about by means of that agent.

IF water had been the menstruum by which the consolidating matter was introduced into the interstices of strata, masses of those bodies could only be found consolidated with such substances as water is capable of dissolving; and these substances would be found only in such a state as the simple separation of the dissolving water might produce.

IN this case, the consolidation of strata would be extremely limited; for we cannot allow more power to water than we find it has in nature; nor are we to imagine to ourselves unlimited powers in bodies, on purpose to explain those appearances, by which we should be made to know the powers of nature. Let us, therefore, attend, with every possible circumspection, to the appearances of those bodies, by means of which we are to investigate the principles of mineralogy, and know the laws of nature.

THE question now before us concerns the consolidating substances of strata. Are these such as will correspond to the dissolving

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