Strata composed in this manner have been again
consolidated; and now the question is, By what means?
If strata composed of such various bodies had been consolidated, by any
manner of concretion, from the fluidity of a dissolution, the hard and
solid bodies must be found in their entire state, while the interstices
between those constituent parts of the stratum are filled up. No partial
fracture can be conceived as introduced into the middle of a solid mass
of hard matter, without having been communicated from the surrounding
parts. But such partial separations are found in the middle of those
hard and solid masses; therefore, this compound body must have been
consolidated by other means than that of concretion from a state of a
solution.
The Spanish marble already described, as well as many consolidated
strata of siliceous gravel, of which I have specimens, afford the
clearest evidence of this fact. These hard bodies are perfectly united
together, in forming the most solid mass; the contiguous parts of some
of the rounded fragments are interlaced together, as has already been
observed; and there are partial shrinkings of the mass forming veins,
traversing several fragments, but perfectly filled with the sparry
substance of the mass, and sometimes with parts of the stone distinctly
floating in the transparent body of spar.
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