of the Fields of Puteolum, There are vast Caves, hugh Recesses, and vacuities; Stones on Mountains hanging here and there: Also cragged Gapings without bottom, which have often receiv'd them, as they fell in, and buried the mighty Ruine in the deep. For the whole Earth is not solid; but every where gaping, and hollow'd with empty rooms and spaces, and hidden burrows, as it were, whereto subscribes Pliny, Aelian, Lucretius, and other writers of Natural things. For the Fire and Water sweetly conspire together in mu∣tual service, with an inviolable friendship and wedlock, for the good of the whole in their several and distinct private-lodgings, as we may so say, and hidden receptacles; spreading themselves far and wide to a vast largeness, and capacity; which two Associates, and A∣gents of Nature, with pains work and bring about such variety of things we see, of Minerals, Juyces, Marles, Glebes, and other soyls, with ebullitions, and bublings up of Fountains also. As Manilius but now sang to us.
Sith this fire thus shut up in the Caverns of the Earth, agitating it self, when it finds passage, it never leaves penetrating unto some vent, for many hundred Miles, even under the Sea, and unpassable and far fetch'd windings and turnings of the Earth. And acquiring continually greater power, it turns the Earth, and even the very Stones and Mountains, it finds in its way, into easie fuel and nutriment: That except it were restrain'd by the encompassing of the Ocean, and the command of the Omnipotent Deity, it would attract and suck in the universal bulk, of all elementary Nature, into an unquenchable combustion, and Conflagration.
And there is need of such vast quantities of fires, for the uses of the Universe; And 'tis reasonable to think that the Divine Provi∣dence hath made a very great provision of fire in the belly of Na∣ture, whence by long Chimnyes or Funnels, as it were, it might diffuse an infinite heat and fervour for the use of things necessary; and the emolument of the Earth, Men, and Beasts. Just as it hath constituted the vast Sea in such a manner so as to distribute an inde∣ficient plenty of Waters, through the veins and channels of the whole body of the Earth. And as it hath appointed the Waters their bounds, so it hath so attempted and distributed these fires, in the hidden courses and apartments of subterrestrial Nature, that they might neither be suffocated by the infinuating and inflowing Waters of the Ocean, nor transgress their prescribed Limits and Confines: For otherwise, if they should be unlimitted Eruptions, they would soon turn all into Ruines.