Of course all this is very ancient history, far beyond the ken of written records, or even the faintest whisper of tradition, unless, indeed, in the awe with which ancient writers alluded to the Phlegræan fields, fabled in old time to be the gate of hell, we may detect some lingering memory of the horrible convulsion which drove back the sea, and out of its deserted bed reared up this wilderness of ash and craters. But speculations of this kind are rather idle. We had better turn towards the grottoes, which are, at least in part, the work of men whose doings on this earth are known to history. The one, of course, is wholly modern, a construction of our own age for the accommodation of the steam tramway; but the other, through which one walks or drives, is certainly as old as the Emperor Augustus, and has sometimes been supposed to possess an antiquity far greater than that. It seems remarkable that the Romans should have esteemed it easier to bore through the cliff than to make a road across the headland. Indeed, there were villas on Posilipo, and there must surely have been a road of some sort from very early times, though it must be admitted that the founders of Naples did not go to Pozzuoli by the coast as we do. The old road climbed up directly from the city to Antignano, in the direction of Camaldoli, and kept along the ridge as far as possible. The coast road began to be used when the tunnel had been made. Still there must have been at least a track across the headland, and one wonders why the Romans did not improve it, in preference to boring underground. The ease with which the soft stone can be worked may account partially for their choice; but it is not to be forgotten that numberless caves, whether natural or artificial, exist in the cliffs at Posilipo and Pizzofalcone, giving occasion to the quick fancy of the Neapolitans to devise wild tales of buried treasure and of strange fierce beasts which guard it from the greed of men. The old legends of the Cimmerians who dwelt in dark caverns of the Phlegræan fields present themselves to mind in this connection, and without following out this mysterious subject further into the mists which envelope it, we may recognise the possibility that some among these caverns are far older than is commonly believed. Of course the preference of the Romans for tunnelling is explained at once, if we may suppose that by enlarging existing caverns they found their tunnel already partly made. [Illustration: POZZUOLI]