=The Monuments.=--Ancient peoples, like ourselves, built monuments of different sorts: palaces for their kings, tombs for the dead, fortresses, bridges, aqueducts, triumphal arches. Of these monuments many have fallen into ruin, have been razed, shattered by the enemy or by the people themselves. But some of them survive, either because there was no desire to destroy them, or because men could not. They still stand in ruins like the old castles, for repairs are no longer made; but enough is preserved to enable us to comprehend their former condition. Some of them are still above ground, like the pyramids, the temples of Thebes and of the island of Philæ, the palace of Persepolis in Persia, the Parthenon in Greece, the Colosseum in Rome, and the Maison Carrée and Pont du Gard in France. Like any modern monument, these are visible to the traveller. But the majority of these monuments have been recovered from the earth, from sand, from river deposits, and from débris. One must disengage them from this thick covering, and excavate the soil, often to a great depth. Assyrian palaces may be reached only by cutting into the hills. A trench of forty feet is necessary to penetrate to the tombs of the kings of Mycenæ. Time is not the only agency for covering these ruins; men have aided it. When the ancients wished to build, they did not, as we do, take the trouble to level off the space, nor to clear the site. Instead of removing the débris, they heaped it together and built above it. The new edifice in turn fell into ruins and its débris was added to that of more remote time; thus there were formed several strata of remains. When Schliemann excavated the site of Troy, he had passed through five beds of débris; these were five ruined villages one above another, the oldest at a depth of fifty feet. By accident one town has been preserved to us in its entirety. In 79 A.D. the volcano of Vesuvius belched forth a torrent of liquid lava and a rain of ashes, and two Roman cities were suddenly buried, Herculaneum by lava, and Pompeii by ashes; the lava burnt the objects it touched, while the ashes enveloped them, preserving them from the air and keeping them intact. As we remove the ashes, Pompeii reappears to us just as it was eighteen centuries ago. One still sees the wheel-ruts in the pavement, the designs traced on the walls with charcoal; in the houses, the pictures, the utensils, the furniture, even the bread, the nuts, and olives, and here and there the skeleton of an inhabitant surprised by the catastrophe. Monuments teach us much about the ancient peoples. The science of monuments is called Archæology.