that the nave and the aisles of the existing basilica correspond with those of the primitive church; the atrium, however, which dates from the ninth century, and two smaller apses, flanking a new central apse of greater depth than the original, were erected. The altar occupies about the same place as in the time of St. Ambrose, and the columns of the ciborium appear never to have been disturbed; they still rest on the original pavement. The Ambrosian basilica, so called even during the life of its founder, was consecrated under circumstances which recall one of the most momentous episodes in the relations of Church and State in the fourth century. On the death of the Emperor Gratian (383), the Empress Justina, in the name of her son, the young Valentinian II, succeeded to the government of the Western half of the Empire. Justina was a zealous Arian, and Milan, where she took up her residence, was militantly orthodox. As the Arians at the time had no place of worship in Milan, the Empress demanded one from Ambrose; but the Bishop without a moment's hesitation refused to comply with her wish. For more than a year Justina and her advisors endeavoured to attain their object; but the firmness of Ambrose, who was supported by the Catholics of Milan, brought all their exertions to naught. The crisis in the unprecedented contest came during the Holy Week of 386. Ambrose received an order to depart from the city; he replied that he would not desert his flock unless forced to do so. He then proceeded to officiate as usual at the Holy Week services in the new basilica. While these functions progressed, the basilica was surrounded by troops, with the design of seizing the Bishop and the church at one stroke, but the people refused to yield. The doors were closed, and for several days St. Ambrose and the congregation endured a siege. The soldiers, however, were by no means hostile, and many of them joined in the singing of the hymns composed by the Bishop for the occasion. Under these circumstances, practically abandoned by the soldiers as well as by the people, the Empress was forced to yield, and peace was restored. For the story of the exclusion of Theodosius from taking part in the celebration of the liturgy, as well as the submission of the great Emperor, see Ambrose, Saint.
After the final victory of Ambrose over the Arian faction at court, the people requested him to consecrate the basilica, which at its opening had only been dedicated. The Bishop replied that he would do so, could he obtain relics of martyrs. This obstacle was removed, St. Augustine informs us (Confess., IX, vii), by the discovery in the Naborian basilica of the relics of Sts. Gervasius and Protasius, the location of whose tombs was revealed to St. Ambrose in a vision. The translation of these martyrs' relics to the new basilica was made with the greatest solemnity, and served as the crowning triumph of the orthodox over the Arians. In the explorations of 1864 the sarcophagi which in the fourth century contained these relics, as well as the sarcophagus of St. Ambrose, were discovered in the confession of the basilica. The remains of all three saints were found in a porphyry sarcophagus to which they had been transferred, probably in the ninth century, by Archbishop Angilbert II (824–859). Like his contemporary and friend, St. Paulinus of Nola, St. Ambrose adorned the walls of his basilica with frescoes representing various scenes from the Old and New Testament. From the distich inscriptions, composed by St. Ambrose, accompanying each group, we learn what subjects were depicted. Noe, the ark, and the dove recalled a favorite subject of the catacombs, though the symbolic meaning was somewhat different. Abraham was represented contemplating the stars, less numerous than his posterity were destined to be; the same patriarch with Sara, in another scene, was acting as host to Angels. Isaac and Rebecca, two scenes from the life of Jacob, and two from that of Joseph formed part of the cycle from the Old Testament. The New Testament was represented by five scenes: the Annunciation, the conversion of Zaccheus, the Haemorrhoissa, the Transfiguration, and St. John, reclining on the breast of Our Saviour. The altar of the basilica, erected in the first half of the ninth century, is a work of rare merit. The famous brazen serpent stands on a column in the nave, on the left, and is balanced by a cross on the right. This was brought from Constantinople about the year 1001, by Archbishop Arnolf, and placed in the Ambrosian basilica under the supposition that it was the brazen serpent erected in the desert by Moses. Archaeologists regard it as very probably a pagan emblem of Esculapius.
Ambrosian Chant.—The question as to what constitutes Ambrosian chant in the sense of chant composed by St. Ambrose has been for a long time, and still is, a subject for research and discussion among historians and archæologists. When the saint became Bishop of Milan, in 374, he found a liturgy in use which tradition associates with St. Barnabas. It is presumed that this liturgy, which was brought from Greece and Syria, included singing by the celebrant as well as the spoken word and liturgical action. On the other hand, it is certain that the greater part of the chants now used in connection with the Ambrosian, or Milanese, rite, which are frequently designated in the wider sense as Ambrosian chant, originated in subsequent centuries as the liturgy was developed and completed. So far no documents have been brought to light which would prove that the saint composed anything except the melodies to most of his hymns. Of a large number of hymns attributed to him, only fourteen are pronounced with certainty to be his, while four more may be assigned to him with more or less probability. Like any other great man who dominates his time, St. Ambrose had many imitators, and it so happened that hymns written by his contemporaries or those who came after him, in the form which he used, that is, the Iambic dimeter, were called "Hymni Ambrosiani". The confusion brought about in the course of time by the indiscriminate use of this designation has necessitated endless study and research before it was decided with any degree of certainty which hymns were by St. Ambrose and which by his imitators. As regards the melodies, it has been equally difficult for archæologists to distinguish them and restore them to what was probably their original form.
Although the opinion that the early Western Church received into her liturgy, together with the psalms of the Old Testament, the melodies to which they had been sung in the Temple and the synagogues, and that melismatic chants (those in which many notes may be sung to one syllable of the text, in contradistinction to syllabic chants, in which there is only one note for each syllable) were in use from the beginning, has been defended with plausibility by men like Hermesdorf, Delitzsch, and, lately, by Houdard (Cantilène Romaine, 1905), no direct contemporary testimony that such was the case has yet been discovered. It is likely that the florid, or melismatic, style in which most of our Gregorian propria are written, and which many authorities hold to be of Hebrew origin, found its way into the Church at a much later period. The literature at the time of St. Ambrose shows that the Greek music was the only kind known to the saint and his contemporaries. St. Augustine, who wrote his unfinished work
