With the conquest of Carthage, Greece, and Egypt, the Romans became acquainted with the arts of those subjugated countries, and tried to improve upon and use them for the em bellishment of the imperial city, and it was most likely their innate desire for improvement that led to the burning of brick in kilns.
Although burnt brick were used in the tower of Babel, and to face the adobes used in the building of the walls and palaces of Babylon, it is probable that the credit of first burning brick in kilns belongs to the Romans ; but it is hard to fix the time when this improvement took place.
Layers of thin brick, separating the tufa surface into panels, called opus reticulaturn, were used in the time of Augustus. In the time of Nero the walls were faced entirely with excellent brick-work, called opus lateritium.
Pliny says that the brick made in Greece at this time were very inferior, and not fit to be used in the construction of a Roman dwelling, and that no party-wall was allowed to be more than eighteen inches in thickness, and that the material would not support one story.
The brick must have been of a very poor quality, or else Pliny greatly misjudged their strength, for at the present time many buildings are being constructed four or five stories high, with the party-walls for most of the way only nine inches in thickness, of the poorest kind of " salmon " brick, from which the water has barely been driven out by the action of the heat ; and if Pliny could see some of the brick now used he would quake for the safety of the occupants of some modern hotels, apartment-houses, office-buildings, and dwellings that have re cently been erected for speculative purposes in London and some portions of this country.
In the first century of the Christian era the brick were better than at other periods ; they were large, flat, and thin, generally two feet square and one inch thick, and were what we call Roman tiles, but were used for building walls, and not merely for roofing or pavements ; the facing brick were triangular, the broad side being outwards. But brick gradually became thicker and shorter, until in the fourth century they were very often as many as four to a foot on the face of the wall, which is about the same as in modern structures.
The Romans did not build their walls entirely of brick; they were used only as a facing or veneering, the same as we use front or pressed brick, the remainder or backing of a wall being of concrete, and thus we find that a large number of the great Roman buildings are constructed of concrete, faced with brick.
The brick-work of the first two centuries of the Christian era, the crowning period of art in Rome, was superior to any other. In the third century there was barely a perceptible change, but in the fourth there was a most decided deterioration, and brick work went back with the times, old material being re-used ex tensively, as in the arch of Constantine.
Knowledge of the art of brick-making has probably at no time become entirely extinct in the East, but after the fourth century, in sympathy with the decline of all other arts, and the dying Roman civilization, the knowledge of this art gradually expired, and was lost to Western Europe.
The Romans made brick extensively in Germany and Eng land, and though it might seem strange that such an art, when once acquired, should have been lost, nevertheless the remains of buildings between the Roman times and the thirteenth cen tury show no evidence of brick having been made in England. In a few instances only were they re-used as old material from buildings left by the Romans, as at Colchester and St. Alban's Abbey—the old Roman town of Verulamium, near which the latter is situated, supplying material for it.
The buildings of the Anglo-Saxons were usually of wood, rarely of stone until the eleventh century, and it is not improb able that the primitive English churches may be among the earliest stone buildings of Western Europe, after the time of the Romans. In these buildings the arches are generally plain, but sometimes they are worked with rude but massive mould ings. Some arches are constructed of brick, all of them taken from some Roman building, as at Bixworth, or sometimes stones are employed, and these usually have a course of brick or thin stones laid upon the top of the arch, as at Britford church, Wiltshire..