=Arcading.=--The arcading, which now became a favourite method of embellishing walls, was of two kinds; either being _open_ and permitting a passageway at the back of them, or with columns and arch mouldings attached to the wall, in the manner known as _blind arcading_. Another feature for strengthening as well as embellishing the wall was the use of masonry piers, which, resting on a plinth, projected from the wall only as far as the width of the cornice. The exteriors, in fact, were no longer, as in early Christian churches, plain and almost barn-like, but assumed a varied picturesqueness that, however, was distinguished by a fine structural unity. The arch, whether used in interior or exterior arcading or for the tops of doors and windows, was round; usually semicircular but occasionally _stilted_, the ends of the semicircle, that is to say, being raised on perpendicular lines. The later introduction of the pointed arch, it may be added, marks the transition from Romanesque to Gothic. A characteristic development of the Romanesque style is the treatment of the doors and windows. The jambs or sides were carried back in a series of angular recesses, which were filled with small columns, whose abaci frequently united in a continuous moulding. In many cases the angular recesses of the jambs were prolonged around the arch. The shafts of columns were decorated with fluting, which might be perpendicular, spiral, or barred like trellis-work. The capitals, except when antique Corinthian or Ionic columns were utilised, display a variety of embellishments, sometimes influenced by Byzantine examples, at other times representing an original working out of foliage motives, often rude in treatment, but, especially in the German work, vigorously decorative. In the nave arcading, that is to say the series of arches on each side of the nave, the supports consisted of square piers, to the faces of which columns were attached. From two of them sprang the arches; a third supported the vaulting of the aisles, while a fourth was run up to a higher level to carry the vaulting of the nave. =Italian Romanesque.=--Since the Romanesque style was coloured by the locality in which it appeared, it is necessary to study examples of it as they are found respectively in Italy, France, the Rhine Provinces, Spain, and England. The Italian examples are conveniently subdivided into those of Northern, Central, and Southern Italy, or, more specifically, into the examples found in the districts north of the River Po, between the Po and the Tiber, and south of the latter. Of these the northern, to be considered later, are the most important, since they show, as we have noted, a more adventurous spirit in the matter of construction.