A. The common base moulding resembles in form or contour a quirked ovolo reversed; there are, however, many exceptions. [Illustration: Norman Base, Romsey Church, Hants.] Q. How are the arches distinguished? A. By their semicircular form; they are generally double-faced, or formed of two concentric divisions, one receding within the other. Early in the style they are plain and square-edged; late in the style they are often found enriched with the zig-zag and roll mouldings, or some other ornament. Sometimes the curvature of the arch does not immediately spring from the capital or impost, but is raised or stilted. Q. What parts of Norman churches do we generally find vaulted? A. In cathedral and large conventual churches built in the Norman style we find the crypts and aisles vaulted with stone, but not the nave or choir; and over the vaulting of the aisles was the triforium. In small Norman churches the chancel is generally the only part vaulted; and between the vaulting and outer roof is, in some instances, a small loft or chamber. Sometimes we find the original design for vaulting to have been commenced and left unfinished. [Illustration: Norman Arch and Piers, Melbourne Church, Derbyshire.] Q. Of what description was the Norman vaulting? A. The bays of vaulting were generally either squares or parallelograms, though sometimes not rectangular in shape, and each was divided into four concave vaulting cells by diagonal and intersecting groins, thus forming what is called a quadripartite vault. Early in the style the diagonal edges of the groins appear without ribs or mouldings; at an advanced stage they are supported by square-edged ribs of cut stone; and late in the style the ribs and groins are faced with roll or cylinder mouldings. They are also sometimes profusely covered with the zig-zag moulding and other ornamental details. Q. What is observable with respect to Norman masonry? A. In general the walls are faced on each side with a thin shell of ashlar or cut stone, whilst the intervening space, which is sometimes considerable, is filled with grouted rubble. Masses of this grout-work masonry, from which the facing of cut stone has been removed, we often find amongst ruined edifices of early date. Q. Were there any buttresses used at this period? [Illustration: Norman Buttress, Chancel of St. Mary’s, Leicester.]