buttress the nave and provide passage around the interior. The interior of the nave thus rises in three stages, the arcade, the gallery and the clerestory which has windows to light the nave. See cathedral diagram The building is of golden-coloured sandstone which has weathered externally to golden-brown. The roof is of red cedar, that of the nave being of an open arch-braced construction enlivened by decorative pierced carvings. The chancel is vaulted with timber, which was probably intended to be richly decorated in red, blue and gold after the manner of the wooden roof at Peterborough, but this did not eventuate, and the warm colour of the timber contrasts well with the stonework. The side aisles are vaulted in stone, with a large round boss at the centre of each ribbed vault. Children who, over the years, have crawled into the arched space beneath the pulpit have discovered another such beautiful carved boss, in miniature and usually unseen. On all the terminals of arches within the buildings are carved heads of saints. Those that are near the confessionals are at eye-level and may be examined for their details. The screen behind the high altar is delicately carved in Oamaru limestone from New Zealand. It contains niches filled with statues like the similar niches in the altar of Our Lady located directly behind it. There are two large chapels and two smaller ones, the larger being the Chapel of the Sacred Heart and the Chapel of the Irish Saints. On either side of the Lady Chapel are the Chapels of Ss Joseph and Peter all with ornately carved altars and a small statue in each niche. The embellished mosaics in the Kelly Chapel floor were laid by Melocco Co. in 1937 approximately the same time as the mosaic floor in the Lady Chapel of St John's College also designed by Wardell. Lighting Because of the brightness of Australian sunlight, it was decided at the time of construction to glaze the clerestory with yellow glass. This glazing has darkened over the years, permitting little light to enter. The yellow glazing contrasts with the predominantly blue stained glass of the lower windows. To counteract the darkness, the cathedral installed extensive lighting in the 1970s, designed to give more-or-less equal illumination to all parts of the buildings. The interior is lit with a diffuse yellow glow, which, like the upper windows, is in