in the porch of the church, before it was moved into the church itself. After the 9th century, with infant baptism increasingly the rule, few baptisteries were built. Some of the older baptisteries were so large that there are accounts of councils and synods being held in them. They had to be large because a bishop in the early church would customarily baptize all the catechumens in his diocese and the rite was performed only three times a year, on certain holy days. Baptisteries were thus attached to the cathedral and not to the parish churches. During the months when no baptisms occurred, the baptistery doors were sealed with the bishop's seal, a method of controlling the orthodoxy of all baptism in the diocese. Some baptisteries were divided into two parts to separate the sexes; or sometimes the church had two baptisteries, one for each sex. A fireplace was often provided to warm the neophytes after immersion. Though baptisteries were forbidden to be used as burial-places by the Council of Auxerre (578), they were sometimes used as such. The Florentine Antipope John XXIII was buried in the Baptistery, facing Florence's Duomo, with great ceremony. A tomb was erected here. Many of the early archbishops of Canterbury in England were buried in the baptistery at Canterbury. According to the records of early church councils, baptisteries were first built and used to correct what were considered the evils arising from the practice of private baptism. As soon as Christianity had expanded so that baptism became the rule, and as immersion of adults gave place to sprinkling of infants, the ancient baptisteries were no longer necessary. They are still in general use, however, in Florence and Pisa. The Lateran Baptistery must be the earliest ecclesiastical building still in use. A large part of it remains as built by Constantine. The central area, with the basin of the font, is an octagon around which stand eight porphyry columns, with marble capitals and entablature of classical form. Outside these are an ambulatory and outer walls forming a larger octagon. Attached to one side, toward the Lateran basilica, is a porch with two noble porphyry columns and richly carved capitals, bases and entablatures. The circular church of Santa Costanza, also of the 4th century, served as a baptistery and contained the tomb of the daughter of Constantine. This is a remarkably perfect structure with a central