Saya mau tau Walls dari Katedral St Paul. Jelaskan dalam bahasa melayu

The building is of two storeys of ashlar masonry, above a basement, and surrounded by a balustrade above the upper cornice. The balustrade was added, against Wren's wishes, in 1718. The internal bays are marked externally by paired pilasters with Corinthian capitals at the lower level and Composite at the upper level. Where the building behind is of only one storey (at the aisles of both nave and choir) the upper storey of the exterior wall is sham. It serves a dual purpose of supporting the buttresses of the vault, and providing a satisfying appearance when viewed rising above buildings of the height of the 17th century city. This appearance may still be seen from across the River Thames.

Between the pilasters on both levels are windows. Those of the lower storey have semi-circular heads and are surrounded by continuous mouldings of a Roman style, rising to decorative keystones. Beneath each window is a floral swag by Grinling Gibbons, constituting the finest stone carving on the building and some of the greatest architectural sculpture in England. A frieze with similar swags runs in a band below the cornice, tying the arches of the windows and the capitals. The upper windows are of a restrained Classical form, with pediments set on columns, but are blind and contain niches. Beneath these niches, and in the basement level, are small windows with segmental tops, the glazing of which catches the light and visually links them to the large windows of the aisles. The height from ground level to the top of the parapet is approximately 110 feet.