It may excite surprise that what appears to be so small a difference as that which exists between a beam, a round arch, or a pointed arch, should be employed in order to distinguish three of the four great divisions. But in reality this is no pedantic or arbitrary grouping. The mode in which spaces or openings are covered lies at the root of most of the essential differences between styles of architecture, and the distinction thus drawn is one of a real, not of a fanciful nature.
Every building when reduced to its elements, as will be done in both these volumes, may be considered as made up of its (1) floor or plan, (2) walls, (3) roof, (4) openings, (5) columns, and (6) ornaments, and as marked by its distinctive (7) character, and the student must be prepared to find that the openings are by no means the least important of these elements. In fact, the moment the method of covering openings was changed, it would be easy to show, did space permit, that all the other elements, except the ornaments, were directly affected by the change, and the ornaments indirectly; and we thus find such a correspondence between this index feature and the entire structure as renders this primary division a scientific though a very broad one. The contrast between the trabeated style and the arched style may be well understood by comparing the illustration of the Parthenon which forms our frontispiece, or that of the great temple of Zeus at Olympia (Fig. [4]), with the exterior of the Colosseum at Rome (Fig. [5]), introduced here for the purposes of this comparison.
Fig. 4.—Temple of Zeus at Olympia. Restored according to Adler.
A division of buildings into such great series as these cannot, however, supersede the more obvious historical and geographical divisions. The architecture of every ancient country was partly the growth of the soil, i.e. adapted to the climate of the country, and the materials found there, and partly the outcome of the national character of its inhabitants, and of such influences as race, colonisation, commerce, or conquest brought to bear upon them. These influences produced strong distinctions between the work of different peoples, especially before the era of the Roman Empire. Since that [!-- original location of Fig. 4 --] period of universal dominion all buildings and styles have been influenced more or less by Roman art. We accordingly find the buildings of the most ancient nations separated from each other by strongly marked lines of demarcation, but those since the era of the Empire showing a considerable resemblance to one another. The circumstance that the remains of those buildings only which received the greatest possible attention from their builders have come down to us from any remote antiquity, has perhaps served to accentuate the differences between different styles, for these foremost buildings were not intended to serve the same purpose in all countries. Nothing but tombs and temples have survived in Egypt. Palaces only have been rescued from the decay of Assyrian and Persian cities; and temples, theatres, and places of public assembly are the chief, almost the only remains of architecture in Greece.
A strong contrast between the buildings of different ancient nations rises also from the differing point of view for which they were designed. Thus, in the tombs and, to a large extent, the temples of the Egyptians, we find structures chiefly planned for internal effect; that is to say, intended to be seen by those admitted to the sacred precincts, but only to a limited extent appealing to the admiration of those outside. The buildings of the Greeks, on the other hand, were chiefly designed to please those who examined them from without, and though no doubt some of them, the theatres especially, were from their very nature planned for interior effect, by far the greatest works which Greek art produced were the exteriors of the temples.
Fig. 5.—Part of the Exterior of the Colosseum, Rome. (Now in Ruins.)