ARCHITECTURE. 127 
floors were inlaid with stone plates of various colors, and an excellent effect 
was attained by grouping the marble, granite, and porphyry plates in rich 
patterns. . 
The roof of the basilica was of simple, double, or triple suspension frame- 
work, according to the size of the main nave, and often without wainscoting, 
so that the rafters were visible in the interior. They were therefore painted 
with great elegance. 
The altar in the oldest basilicas was of the shape of a quadrangular 
sarcophagus, emblematic of the holy sepulchre. The attributes of Chris- 
tianity, the alpha and omega, labarum, palm tree, cross, &c., were among 
the decorative sculptures of the altar. In basilicas dedicated to sainted 
martyrs their remains were deposited in the altars, which also received a 
niche in which a relic of the martyr was placed. 
Sometimes subterranean chapels were constructed under the altars, and 
adorned with the richest embellishments. They were approached by steps 
from the interior of the basilica. At the four corners of the altar stood 
columns which supported an entablature and ceiling, forming a canopy over 
the altar. This canopy was termed ciborium. Pl. 27, fig. 19, shows that 
in the basilica San-Clemente in Rome, and under it the entrance to the 
subterranean chapel. 3 
The part of the basilica lying in front of the sanctuary was set apart by 
low partitions of richly carved wood or marble, and sometimes raised several 
steps above the level of the naves. This was the choir, or high choir, which 
had benches of wood or marble, and a pulpit. /%g. 20 represents the 
high choir of San Clemente. 
In some of the basilicas there is erected a small distinct building dedicated 
to the ceremony of baptism, and termed baptistery; more frequently, how- 
ever, these buildings were erected in front of the main entrances of basilicas. 
They were of various forms (jigs. 21-24). They contained in the centre a 
deep basin or pool, usually corresponding in form with the ground plan of 
the building, and the baptismal rite was performed by immersion, amid invo- 
cations of St. John the Baptist. Subterranean conduits supplied and drained 
the pool. Sometimes it was surrounded with columns, which supported the 
ceiling, as in that of St. Agnes in Rome (jig. 29). Afterwards the baptisteries 
were united with the basilicas themselves, and then occupied the head of 
the side aisle, set apart by a railing and a portico, as in the basilica in 
Cividale, of whose baptistery jig. 28 gives a view. The ceremony of total 
immersion ceased after the baptistery had become part of the church proper. 
Baptismal fonts were then introduced, of which jigs. 25-27 give the most 
usual forms. They were large enough for several persons to be baptized 
standing at the same time. ‘The smaller baptismal fonts were not introduced 
until several hundred years later, when immersion had been altogether set 
aside. 
4. DescrirTion oF sOME RomANESQUE Basmicas. The oldest basilica 
built by Constantine in Rome is St. John Lateran. It had the Roman 
form and four rows of antique columns in the interior. These beautiful 
Tonic columns have disappeared under casings of pilasters made in the 
127 
