SPIRE, in architecture, a steep, pyramidal form, crowning a tower. The origin of the form was the simple, four-sided, pyramidal roof frequently erected over Romanesque towers, as in many crude iith century examples in Normandy, some of the Italian campaniles of the nth and 12th centuries, and many German Romanesque towers, mostly of the 12th century. This form is abrupt and stunted and may easily be ungraceful, and various experimental attempts were made to soften the line. Thus the late 11th century tower at Le Puy en Velay has the successive stages of the tower receding and broken up by project ing bays on the sides. Furthermore, the pyramidal roof itself is decorated with corner finials and small, round-headed dormers. In Germany the form was varied by ending each face of the square tower in a gable, the plane determined by adjacent gable slopes establishing the slope of the pyramid, as in the square tower of the abbey church of Laach (c. 1156). The pleasanter effect of the octagonal spires over octagonal towers, like another of the towers at Laach, or the older of the two towers at Mainz (late 12th century), led to attempts to combine an octagonal spire with a square tower. This was accomplished in various ways, one of the simplest being the so-called broach spire, in which small, triangular planes of a less steep pitch than that of the spire proper occur at the bottom of the corner spire faces, with their lower points coinciding with the corners of the towers, as seen in the 12th century church of S. Columba at Cologne.
A more developed form of broach spire lies in the substitution of a small pyramid at the bottom of the corner faces, instead of the triangular plane. This is a type which became common in English Gothic spires. It may be described geometrically as the intersection of a four-sided pyramid of low slope by an eight-sided Pyramid of steep slope, as in the 14th century spire of St. Mary's at Stamford. A more elaborate method of softening the junction between square and octagon was to carry the corner faces down unbroken to the top of the tower and fill the triangular corners thus left with decorative finials. An early example is the crossing
tower of the church of S. Ours, at Loches, France (12th century).
In the south-west tower of Chartres cathedral (end of the i2th century) a further advance is made in connecting tower and spire, by adding high, gabled dormers on the faces of the spire, over the centres of the tower faces, as well as richly developing the corner pinnacles. In the spire at Senlis cathedral (13th century) a ver tical, octagonal stage, or lantern, is placed between the square tower and the octagonal spire. The corners of the square tower are occupied by pinnacles and eight slim dormers surround the spire base. The edges of the Chartres and Senlis spires are dec orated with projecting roll mouldings, and those at Senlis are further enriched by crockets which form an admirable fretting of the silhouette. It is probable that similar crocketed spires were almost universally intended over the great towers of most of the French cathedrals. The towers at Laon, for instance, were once so crowned and spires at Reims and Amiens were begun.