e and singular veins which you see at the base and rising
through the substance of the strata are composed of volcanic porphyry,
and offer a most striking and beautiful example of the generation and
structure of rocks and mineral formations.

_Onuphrio_.--As we passed through Portici, on the road to the base of
Vesuvius, it appeared to me that I saw a stone which had an ancient Roman
inscription upon it, and which occupied the place of a portal in the
modern palace of the Barberini.

_Phil_.--This is not an uncommon circumstance: Most of the stones used in
the palaces of Portici had been employed more than two thousand years
before in structures raised by the ancient Romans or Greek colonists; and
it is not a little remarkable that the buildings of Herculaneum, a town
covered with ashes, tufa, and lava, from the first recorded eruption of
Vesuvius more than seventeen hundred years ago, should have been
constructed of volcanic materials produced by some antecedent igneous
action of the mountain in times beyond the reach of history; and it is
still more remarkable that men should have gone on for so many ages
making erections in spots where their works have been so often destroyed,
inattentive to the voice of time or the warnings of nature.

_Onu_.--This last fact recalls to my recollection an idea which
Philalethes started in the remarkable dream which he would have us
believe occurred to him in the Colosaeum, namely--that no important facts
which can be useful to society are ever lost; and that, like these
stones, which though covered with ashes or hidden amongst ruins, they are
sure to be brought forward again and made use of in some new form.

_Amb_.--I do not see the justness of the analogy to which Onuphrio
refers; but there are many parts of that vision on which I should wish to
hear the explanations of Philalethes. I consider it in fact as a sort of
poetical epitome of his philosophical opinions, and I regard this vision
or dream as a mere web of his imagination in which he intended to catch
us, his summer-flies and travelling companions.

_Phil_.--There, Ambrosio, you do me wrong. I will acknowledge, if you
please, that the vision in the Colosaeum is a fiction; but the most
important parts of it really occurred to me in sleep, particularly that
in which I seemed to leave the earth and launch into the infinity of
space under the guidance of a tutelary genius. And the origin and
progress of civil society for