by Innocent VIII (1484–92). Acquaxava, a town of the Campagna, was declared similarly exempt by Pius IX and united with Altamura, 17 August, 1848. Altaiuura has 4 parishes and a Catholic population of 19,333; Acquaviva has one parish and a Catholic population of 8,527; the clergy number 80.
BATTANDIER, Ann. Pont. (1905), 338.
Altar (in Liturgy).—In the New Law the altar is the table on which the Eucharistic Sacrifice is offered. Mass may sometimes be celebrated outside a sacred place, but never without an altar, or at least an altar-stone. In ecclesiastical history we find only two exceptions: St. Lucian (312) is said to have celebrated Mass on his breast whilst in prison, and Theodore Bishop of Tyre on the hands of his deacons (Mabillon, Præf. in 3 sæc., n. 79). According to Radulphus of Oxford (Prop. 25), St. Sixtus II (257–259) was the first to prescribe that Mass should be celebrated on an altar, and the rubric of the missal (XX) is merely a new promulgation of the law. It signifies, according to Amalarius (De Eccles. Officiis, I, xxiv) the Table of the Lord (mensa Domini), referring to the Last Supper, or the Cross (St. Bernard, De Coenâ Domini), or Christ (St. Ambrose, IV, De Sacram. xii; Abbot Rupert, V, xxx). The last meaning explains the honour paid to it by incensing it, and the five crosses engraved on it signify His five wounds.
Position.—In the ancient basilicas the priest, as he stood at the altar, faced the people. The basilicas of the Roman Empire were, as a rule, law courts or meeting places. They were generally spacious, and the interior area was separated by two, or, it might be, four rows of pillars, forming a central nave and side aisles. The end opposite the entrance had a semi-circular shape, called the apse, and in this portion, which was raised above the level of the floor, sat the judge and his assessors, while right before him stood an altar upon which sacrifice was offered before beginning any important public business. When these public buildings were adapted for Christian assemblies, slight modifications were made. The apse was reserved for the bishop and his clergy; the faithful occupied the centre and side aisles, while between the clergy and people stood the altar. Later on the altar was placed, in churches, in the apse against, or at least near, the wall, so that the priest when celebrating faced the east, and behind him the people were placed. In primitive times there was but one altar in each church. St. Ignatius the Martyr, Cyprian, Irenaeus, and Jerome, speak of only one altar (Benedict XIV, De Sacr. Misssæ, § 1, xvii). Some think that more than one altar existed in the Cathedral of Milan in the time of St. Ambrose, because he sometimes uses the word altaria, although others are of opinion that altaria in this place means an altar. Towards the end of the sixth century we find evidence of a plurality of altars, for St. Gregory the Great sent relics for four altars to Palladius, Bishop of Saintes, France, who had placed in a church thirteen altars, four of which remained unconsecrated for want of relics. Although there was only one altar in each church, minor altars were erected in side chapels, which were distinct buildings (as is the custom in the Greek, and some Oriental Churches even at the present day) in which Mass was celebrated only once on the same day in each church (Benedict XIV, Ibidem). The fact that in the early ages of Christianity only the bishop celebrated Mass, assisted by his clergy, who received Holy Communion from the bishop's hands, is the reason that only one altar was erected in each church, but after the introduction of private Masses the necessity of several altars in each church arose.
Material Of Altars.—Although no documents are extant to indicate the material of which altars were made in the first centuries of Christianity, it is probable that they were made of wood, like that used by Christ at the Last Supper. At Rome such a wooden table is still preserved in the Lateran Basilica, and fragments of another such table are preserved in the church of St. Pudentiana, on which St. Peter is said to have celebrated Mass. During the persecutions, when the Christians were forced to move from one place to another, and Mass was celebrated in crypts, private houses, the open air, and catacombs, except when the arcosolia were used (see below, Form of an Altar), it is but natural to suppose that they were made of wood, probably wooden chests carried about by the bishops, on the lid of which the Eucharistic Sacrifice was celebrated. St. Optatus of Mileve (De Schismate Donatistarum) reproves the Donatists for breaking up and using for firewood the altars of the Catholic churches, and St. Augustine (Epist. clxxxv) reports that Bishop Maximianus was beaten with the wood of the altar under which he had taken refuge. We have every reason to suppose that in places in which the persecutions were not raging, altars of stone also were in use. St. Gregory Thaumaturgus in the third century built a vast basilica in Neo-Cæsarea in which it is probable that more substantial altars were erected. St. Gregory of Nyssa speaks of the consecration of an altar made of stone (De Christi Baptismate). Pulcheria, sister of Theodosius II, presented an altar of gold to the Basilica of Constantinople; St. Helena gave golden altars ornamented with precious stones to the church which was erected on the site where the Cross had been concealed for three hundred years; the Popes St. Sixtus III (432–440) and St. Hilary (461–468) presented several altars of silver to the churches of Rome. Since wood is subject to decay, the baser metals to corrosion, and the more precious metals were too expensive, stone became in course of time the ordinary material for an altar. Besides, stone is durable and, according to St. Paul (I Cor., x, 4), symbolizes Christ—"And the rock was Christ". The Roman Breviary (9 November) asserts that St. Sylvester (314–335) was the first to issue a decree that the altar should be of stone. But of such a decree there is no documentary evidence, and no mention is made of it in canon law, in which so many other decrees of this Pope are inserted. Moreover, it is certain that after that date altars of wood and of metal were erected. The earliest decree of a council which prescribed that an altar which is to be consecrated should be of stone is that of the provincial council of Epeaune (Pamiers), France, in 517 (Labbe, Concil. tom. V, col. 771). The present discipline of the Church requires that for the consecration of an altar it must be of stone.
Form Of An Altar.—In the primitive times there were two kinds of altars. (1) The arcosolium or monumentum arcuatum, which was formed by cutting in the tufa wall of the wider spaces in the catacombs, an arch-like niche, over a grave or sarcophagus. The latter contained the remains of one or several martyrs, and rose about three feet above the floor. On it was placed horizontally a slab of marble, called the mensa, on which Mass was celebrated. (2) The altar detached from the wall in the cubicula, or sepulchral chapels surrounded by loculi and arcosolia, used as places of worship in the catacombs or in the churches erected above ground after the time of Constantine. This second kind of altar consisted of a square or oblong slab of stone or marble which rested on columns, one to six in number, or on a structure of masonry in which were enclosed the relics of martyrs. Sometimes two or four slabs of stone were placed vertically under the table, forming a stone chest. In private oratories the table was sometimes made of wood and rested on a wooden support. Within this support were placed the relics of martyrs, and in order to
