But from the second century of our era there was celebrated in the western part of the Roman Empire another mystic rite in the worship of the Great Mother to which we must now turn our attention for a moment. I mean that ritual of purification and regeneration by means of the blood of a slain bull which the ancients called the _taurobolium_. Without much doubt this rite developed from the sacrifice of a bull to the Great Mother, such as was made annually on March 15 at Rome. But the taurobolium was no ordinary sacrifice. It is first mentioned in the west in an inscription from Puteoli of 134 A.D.;[295] thence it quickly spread to Rome, from there to Lyons; and it was celebrated in many parts of the western provinces during the second and third centuries. Like the other oriental rites it lived on at Rome long after it had died in the provinces, the last celebration being near the close of the fourth century. One of the earliest places at Rome for the performance of the taurobolium was in the Vatican district close by the circus erected by the Emperor Caligula and enlarged by Nero. There, certainly from the time of Antoninus Pius to the end of the fourth century, this purifying and regenerating ritual was performed, never with more passionate hope of its efficacy than during the fourth century, when for some seventy years this pagan shrine and St. Peter’s first basilica stood side by side, fanes of the dying faith and of the triumphing religion. It stirs the imagination to recall that when in the early seventeenth century certain changes were being made in the present St. Peter’s, a considerable number of inscriptions were discovered buried in the ground, recording the celebration of the taurobolium by members of the nobility after the first St. Peter’s had been built.[296] So side by side the two rival religions contended for the mastery. The two descriptions of the ritual we have date from the fourth century.[297] The one who was to be purified, after first laying aside his ordinary garments and dressing himself in rags as a suppliant and beggar, descended into a pit. This was covered with planks pierced with holes; then the sacred bull was slain over the planks that his blood, falling on the devotee, might cleanse him and give him freedom from his sin. The recipient endeavored to have every part of his person—especially his eyes, nose, and ears—washed by the cleansing streams; he opened his mouth to catch the falling blood and swallowed it. When he issued forth from the pit, dripping with his horrible purification, he was greeted by his fellow consecrates as one who had been born again. Usually the efficacy of the new birth given by the taurobolium was thought to last only twenty years (renatus in XX annos), at the expiration of which time the ritual was apparently repeated;[298] once, however, we have the confident assertion that the devotee was “born again for eternity.”[299]