Roman Arch and Columns
It is sometimes said that the arch originated with the Romans. This should be differently stated; the arch itself they did not originate, but they applied it with great skill and success to various works of utility, and made it a universal feature in civil buildings. Their triumphant use of the arch was reached, however, in the dome of the Pantheon, which edifice may in a sense be claimed as an example of a new style of architecture. Its simple grandeur has not been surpassed. Its style demanded the invention of appropriate details, which the Romans failed to produce; but the Pantheon and the ruined Temple of Peace were the two Roman edifices which indicated the progress of the Romans towards the invention of an architecture distinctively their own.
The Romans not only demonstrated their power to adapt what already existed to many purposes in their use of the arch, but in that of the various orders of architecture also; they not only employed these in ways not before known, but they combined features of different orders, and created the so-called composite capitals and bases. In the Colosseum, for example, we see two styles most inappropriately used. The entire structure is arched, and a net, as it were, of Grecian columns, supporting an entablature, applied to it. The first glance reveals its faults, and a regret that buttresses were not used is involuntary; these would appear to sustain the whole, and would have added an effect of vast strength as a constructive element; while the columns used have the effect of sustaining the entablature only, and of adding their own burden to what the arches already had to bear.
The Roman Doric, derived from the Greek, differs from it through the introduction of an independent base, and certain ornamental additions to the capital. This order was used in Roman forums, courtyards, etc., and in the three-quarter columns in arcades, as well as for useful supports in civil buildings; but no purely Greek temple existed in the entire Roman territory. It would seem that these exquisite edifices, in the perfection of Greek refinement, were too sublimated in effect to please the ruder Romans.
The Ionic order suffered absolute degradation at the hands of the Romans, who appear neither to have understood nor appreciated this column. However, their structures were so lofty that they found it necessary to use the three orders of pillars, one above the other, and so placed the Ionic in the centre. Two capitals from the Temple of Concord, now in the Palace of the Conservators, having a pair of rams' heads at each corner, show the degeneration to which Ionic capitals were subjected. It is to be deplored that the two orders which had reached perfection in Greece were not appreciated and properly used at Rome.
With the Corinthian order it was quite different. That was still incomplete in the estimation of the Hellenes; for while exquisite in design and grace, the Greeks had not given it the strength which is an indispensable feature of a supporting architectural member. This the Romans accomplished, or perhaps it would be more just to say that Greek artists perfected this order in Rome. Within the Roman territory the Corinthian order underwent many modifications; and it is stated that as many as fifty varieties of Corinthian capitals were produced for Roman uses during the three fruitful centuries mentioned above. They vary from the elegant simplicity of the Greek artistic taste to that florid ornamentation loved by the Romans. Those in the portico of the Pantheon have fine capitals, not over-ornamented; but the incongruity of a plain shaft with a Corinthian capital affords an example of Roman methods.
The composite capitals of the Romans combined the lower half of the Corinthian with the upper half of the Ionic capital. Although the result was a rich and strong capital, it had the grave defect of exposing the junction of the two portions, and never became popular.
The Assyrian base was introduced at Rome too late for the perfection of such a column as might have been made with it, together with a Composite or Corinthian capital. This base was used in the church of S. Prassede, and one can imagine that for internal architecture it would be very acceptable with either an Ionic or Corinthian column.
Another use of a composite architecture, made by the Romans, was that of placing two columns about as far apart as they were high, and resting a long entablature on them, which, requiring a support, was supplemented by an arch resting on piers. A keystone projecting from the arch to support the entablature was necessarily longer and heavier than was in keeping with the proportions of the arch; and the whole arcade thus produced was clumsy and unsatisfactory. Various experiments for its improvement resulted in abolishing the piers and springing the arch from the pillars themselves; very handsome and dignified arcades were constructed in this manner.
Without reviewing the different steps in the advance from wooden huts and mounds of earth, such as were used in the earliest years at Rome, to the splendid architecture gradually developed there, we may say that not until an acquaintance with the Greeks gave them models from which to work, and introduced to them such tools as they had not before seen, was any use made of stone, or, in fact, anything accomplished that merited the name of architecture. From the Greeks the Romans borrowed not only orders and designs, but also the ordinary methods and implements of construction, such as the preparation of mortar, the artificial lattice-work, the measuring-rod, and the use of iron, which they had not before known.