_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 form likewise parts of another dream which I had many years ago, and it was in the reverie which happened when you quitted me in the Colosaeum that I wove all these thoughts together, and gave them the form in which I narrated them to you. _Amb_.--Of course we may consider them as an accurate representation of your waking thoughts. _Phil_.--I do not say that they strictly are so, for I am not quite convinced that dreams are always representations of the state of the mind modified by organic diseases or by associations. There are certainly no absolutely new ideas produced in sleep, yet I have had more than one instance, in the course of my life, of most extraordinary combinations occurring in this state, which have had considerable influence on my feelings, my imagination, and my health.