aequora pendenti margine summa ligat.
Viva coronatos adstringit scaena vapores, 45
et levis exili cortice terra natat
calcantumque oneri numquam cessura virorum
sustentat trepidum, fida ruina, pedem.
facta manu credas, sic levis circuit oras
ambitus et tenuis perpetuusque riget. 50
they—so tradition tells—of Hercules’ plough, or else chance did the ploughshare’s work. In the middle of the hill is what seems a broad, steaming sea, an azure lake of vast extent. Great is the space it covers, still greater its depth where it plunges down and loses itself beneath the rocky caverns. A thick pall of steam hangs over it; its waters cannot be touched nor drunk though they are transparent as crystal to the very bottom. Nature took counsel for herself and lest that lake should be entirely beyond our ken she let our eyes penetrate what, because of its heat, our bodies could not enter. When a breeze scatters the thick clouds of steam and clears the grey surface of the erstwhile vaporous water you can gaze with wonder on the valley floor below that glassy flood where glint old weapons, king’s gifts[87] of bygone days (between these a gulf of other hue, dark with the eddyings of black sand, swallows the hastening waters; below there opens a cavern into which the darkling flood pours, filling every nook and cranny with its swirling eddies); then are revealed the hidden places of the hill which, bent round in a bow, encircles the surface of the water with an overhanging rim.[88]
A verdant amphitheatre surrounds this steaming cauldron, and the ground floats lightly with slender film[89]; never will it give way beneath the visitor’s weight, upholding his timorous feet, trusty though seeming so unsure. One would think it the work of man’s hand, so smoothly does its circuit enfold the shore, slight and yet firm all the way. The water