since been an important, often the most important, feature in architectural works.
The Roman architect was thus in possession of all the constructive elements—pillar, architrave, pediment, and arch—which distinguish an architectural edifice from a building merely made up of walls and a roof. Without speculating as to the origin of pillar and architrave, with their subsidiary elements of plinth, capital, cornice, etc., it is clear that the last two—the pediment and the arch—resulted from the pressure of new and external circumstances. Into the history of the orders we need not enter. Their function is that of ornament, and the choice of their forms was probably governed by considerations of taste rather than the requirements of situation. The classic architecture in the best examples presents all the characteristics of a finished and matured art; and if the old civilization had been maintained, in the old places, though an additional order or two might perhaps have been invented for the sake of variety, there is no indication that there would have been any important change in the style of building. The disintegration of the Roman Empire, however, and the triumph of the barbarians, brought into play an entirely new set of forces, and prepared the way for that wonderful series of beautiful and ever-varying creations which we know by the name of Gothic architecture.
Can we discover what it was that inspired the mediæval builders in the production of forms of so much beauty, often at times when all other arts were dead and gross ignorance abounded? One consideration may help us. The periods of the Gothic styles (including those which led up to the styles to which the term is sometimes restricted) are precisely those which are called the dark ages; and in the successive changes through which the art passed in those ages can we not perceive a yearning for light—light in a threefold sense—religious, artistic, and physical?
1. Moral or religious light. An upward tendency now begins to manifest itself. There is an evident disposition to make the buildings appear as if springing up from the earth, instead of resting upon it. In the temples of antiquity all the principal lines are horizontal, in agreement with the surface of the earth; in the mediaeval buildings the tendency of the prevailing lines is to assume a vertical position, pointing heavenward.
2. Artistic lightness. The Greeks and Romans appear to have paid little regard to economy of material in the construction of their public edifices. Many of their works seem to rely for their effect chiefly upon their massive grandeur. But the Gothic architects seem to have been distressed with the weight of the material in which they worked. They found means, from time to time, to diminish its weightiness, in appearance at least, by diapering, molding, and tracery.
3. Physical light. Under the semi-tropical skies of Southern Europe, little regard had to be paid to this blessing, beyond providing
