Somewhere south of the palace and not far from it was a garrison to protect the suburb and the Cité from southern invasion. That it was not greatly needed during this peaceful and prosperous period seems proved by the fact that Lutetia’s amusement ground was not within its easy reach, but on the eastern slope of Mons Lucotetius. Here at some time during the Roman occupation, perhaps during the second or third century, an amphitheater was built, and here emperors and generals and merchants, Romans and Gauls, gazed upon the pageants and contests of the arena. Christianity wrought a milder mood in her believers and even before the invasion of the Franks the stone seats of the ellipse had been converted to other uses. Enough was discovered, however, some thirty [Illustration: INTERIOR OF THE ROMAN PALAIS DES THERMES.] [Illustration: AMPHITHEATER OF LUTETIA AT PRESENT TIME.] years ago to permit an adequate idea of the original appearance. To Julian has been attributed the rebuilding of the Cité, and excavations at different points have unearthed remains unmistakably of Roman workmanship, which show that the island was completely surrounded by a wall. Probably some of the stones of the amphitheater went into it. This fortification has been related to the fourth century, and it is known that on the spot in the Cité where the Palais de Justice now houses the law courts, an administrative building of some kind has stood since this same early date. One of Julian’s successors, Maximus, erected a triumphal arch near the cathedral in 383, and it is probable that other pretentious structures justified the erection of the protecting wall. The cathedral was a church dedicated to Saint Étienne, modest as compared with its medieval successor, Notre Dame, whose sacristy is placed on the same spot, yet showing that concentration of the arts in their expression of religious spirit which has made the churches of Europe at once the treasure-house of the student and the devotee, the inspiration of the poet, and the joy of the lover of color and of line. Both of these Christian churches have stood on ground already dedicated to religion, for under the choir of Notre Dame there was discovered in 1711 a pagan altar, now the chief relic of the museum in the Thermes. The inscription on the stone places it in the reign of the emperor Tiberius (14-37 A.D.), the successor of the great Augustus. Its inscription reads: “When Tiberius was emperor the Parisian Watermen publicly raised this altar to Jupiter, best and greatest.” [Illustration: THE NAUTÆ STONE.]