monly found attached to the cathedral and not to the parish churches),
and also because the rite was performed only thrice in the year. (See
BAPTISM.) During the months when there were no baptisms the baptistery
doors were sealed with the bishop's seal. Some baptisteries were divided
into two parts to separate the sexes; 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 not uncommonly used
as such. Many of the early archbishops of Canterbury were buried in the
baptistery there. Baptisteries, we find from the records of early councils,
were first built and used to correct the evils arising from the practice of
private baptism. As soon as Christianity made such progress that baptism
became the rule, and as soon as immersion gave place to sprinkling, the
ancient baptisteries were no longer necessary. They are still in general
use, however, in Florence and Pisa. The baptistery of the Lateran must be
the earliest ecclesiastical building still in use. A large part of it
remains as built by Constantine. The central area, where is 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,
towards the Lateran basilica, is a fine 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 dome, columns and mosaics of classical
fashion. Two side niches contain the earliest known mosaics of
distinctively Christian subjects. In one is represented Moses receiving the
Old Law, in the other Christ delivers to St Peter the New Law--a charter
sealed with the X P monogram.

Another baptistery of the earliest times has recently been excavated at
Aquileia. Ruins of an early baptistery have also been found at Salona. At
Ravenna exist two famous baptisteries encrusted with fine mosaics, one of
them built in the middle of the 5th century, and the other in the 6th. To
the latter date also belongs a large baptistery decorated with mosaics at
Naples.

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