EARLY CHRISTIAN ARCHITECTURE.
WE have so far left unconsidered the most interesting and the most important department of the art history of the early Middle Ages, viz., its architecture. There are no remains of any buildings in Northern Europe, preceding the Roman period, unless the open-air temple inclosures of the older Celtic time, like Stonehenge on Salisbury Plain in England, should be considered as buildings. We have seen what monuments of architecture were universal in certain European countries under the empire, and we have seen that a century of church building had passed away in direct development from the Roman classic art before the downfall of the Roman Empire in the West.
The changes in architectural style which are apparent after the triumph of Christianity in the empire were not less marked than those which affected the arts of design. It is true that we can hardly point to a surviving church in Northern Europe of earlier date than the eleventh century. Crypts (underground chapels) or small portions of churches built into later ones are occasionally met with. The chapel built by Charlemagne at Aix-la-Chapelle in Germany, now a portion of the later cathedral, and one or two oratories (small chapels) in Ireland are among the rare exceptions. But certain surviving churches of Italy enable us to picture the general style and arrangements of buildings which have disappeared.
Aside from the Church of the Manger at Bethlehem and,