[Illustration:  The Nola Gate at Pompeii.]

It is worth while passing through the gate to get a look at the angle formed by the ramparts at this one point.  I doubt whether the city was ever attacked on that side.  Before reaching the gate the assailants would have had to wind along through a narrow gallery, where the archers, posted on the walls and armed with arrows and stones, would have crushed them all.

The Herculaneum gate is less ancient, and yet more devastated by time than the former one.  The arcade has fallen in, and it requires some attention to reinstate it.  This gate formed three entrances.  The two side ways were probably intended for pedestrians; the one in the middle was closed by means of a portcullis sliding in a groove, still visible, but covered with stucco.  As the portcullis, in descending, would have, thrown down this coating, we must infer that at the time of the eruption it had not been in use for a long while, Pompeii having ceased to be a fortified place.

The Herculaneum gate was not masked inside, so that the archers, standing upon the terraces that covered the side entrances, could fire upon the enemy even after the portcullis had been carried.  We know that one of the stratagems of the besieged consisted in allowing the enemy to push in, and then suddenly shutting down upon them the formidable cataracta suspended by iron chains.  They then slaughtered the poor wretches indiscriminately and covered themselves with glory.

Having passed the gate, we find ourselves on one of those fine paved roads which, starting at Rome in all directions, have everywhere left very visible traces, and in many places still serve for traffic.  The Greeks had gracefulness, the Romans grandeur.  Nothing shows this more strikingly than their magnificent highways that pierce mountains, fill up ravines, level the plains, cross the marshes, bestride rivers, and even valleys, and stretched thus from the Tiber to the Euphrates.  In order to construct them, they first traced two parallel furrows, from between which they removed all the loose earth, which they replaced with selected materials, strongly packed, pressed, and pounded down.  Upon this foundation (the pavimentum) was placed a layer of rough stone (statumen), then a filling-in of gravel and lime (the rudus), and, finally, a third bed of chalk, brick, lime, clay, and sand, kneaded and pounded in together into a solid crust.  This was the nucleus.  Last of all, they placed above it those large rough blocks of lava which you will find everywhere in the environs of Naples.  As before remarked, these roads have served for twenty centuries, and they are good yet.

[Illustration:  The Herculaneum Gate, restored.]