The Triforium Belt.—This used to be called the "Attic," in imitation of the Classical nomenclature; but surely this term is incorrect, since there is a clerestory above, and the vaulting springs from it as well. On the other hand, "Triforium" pure and simple implies arcading, and the above term is adopted from Fergusson as less open to exception.[92] In continuation of the greater pilasters are abutment piers, from the summits of which spring the great arches spanning the nave, the window arches of the clerestory, and the pendentives which connect these with the vaulting. The blank fronts between the piers are relieved by panels, but otherwise destitute of adornment. Openings connect the nave with the galleries behind.
The Clerestory.—This stage again calls for little or no comment. The windows, hidden from the exterior by the curtain wall, are slightly rounded. Above and on either side are sections of spheres, ornamented with festoons. These are the ends of elliptic cylinders in connection with the vaulting.
The Vaulting.—The great arches overhead divide the vault as the greater pilasters and their continuations do the walls. Between these arches are the small saucer-shaped domes, 26 feet in diameter. The reason for these and their accessories, the pendentives, may best be understood from Wren's own words. He says that his method of vaulting is the most geometrical, and "is composed of Hemispheres, and their Sections only; and whereas a Sphere may be cut all Manner of Ways, and that still into Circles ... I have for just Reasons followed this way in the Vaulting of the Church of St. Paul's.... It is the lightest Manner, and requires less Butment than the Cross-vaulting, as well that it is of an agreeable View.... Vaulting by Parts of Hemispheres I have therefore followed in the Vaultings of St. Paul's, and with good reason preferred it above any other way used by Architects."[93] The saucer-shaped domes are sections of spheres, as are both the pendentives and the sides of the clerestory windows. He set to work something in this way. After satisfying himself that he had hit on a better plan than the plain cylindrical or the cross-vaulting of the Romans, or the other forms of intersecting vaults, he seems to have taken a hemisphere as a plan to work upon, and fixed his imaginary centre about the level of the top of the triforium. In the great square western severy of the nave this was easier, but the other severies are oblong. Here he stretched his sections out, so as to include the clerestory windows and their much-needed light. The usual way of expressing this is to say that the vault is intersected across by an elliptic cylinder. The wreaths, garlands, and festoons, and the various conventional patterns with which the edges and surfaces of the various parts of the vaulting is adorned cannot be estimated from the pavement. We may add here that the pendentives were purposely constructed of "sound Brick invested with Stucco of Cockle-shell lime," and not of Portland stone, for further ornament if required.[94] So are the circular sections.
The nave is connected with the dome by the space between the great piers or walls of more than 30 feet in length. These piers are also broader at their ends than those which support the arcading, the latter covering a square of about 10 feet. The greater massiveness is owing to their assistance being required in supporting the dome. They have large pilasters at the angles, and their coffered wagon vaulting, adorned with geometrical patterns, is very striking.
The Nave Aisles.—We will first point out an unnoticed feature in the great piers at either end. Their inner faces as seen from the aisles have recesses or niches for the reception of monuments, and other recesses are generally found in the wall opposite. At the west of the aisles there are eight of these altogether, just behind the coupled columns. They are repeated in all the great piers leading to the dome, but although of sufficient height to permit of the introduction of life-sized effigies, still remain unoccupied. The coupled columns are repeated at the entrances to the chapels. At both ends the perspective is narrowed; at the west by the chapels, at the east by the breadth of the great piers. The windows stand in recesses which are segments of circles. Their sides are made to represent piers with concave surfaces. These latter carry an entablature from which spring the round window arches. Festoons run below the actual windows, the concave side piers have panels, and the round arches above diamond-shaped patterns. There are only three windows on either side—the chapels taking the place of a fourth—and the depth of their recesses points out the thickness of the walls. Between each recess are Composite pilasters in couples, with others opposite against the piers. These correspond with the lesser pilasters of the arcading, and from them spring transverse arches, as in the great central aisle. The vaulting, owing to the severies being nearly square, is regular; in other respects similar to that already described. The height is much less than that of the greater aisle, reaching only to the first stage of the latter.
The West Chapels.—They may best be described as squares of 26 feet, with apses or tribunes at either end which increase the length to 55 feet. They suffer sadly from want of light, the one window in each being altogether insufficient; but Wren had to do what he could. He panelled them with oak, and made them of the same height as the aisles, with vaulting of his favourite kind, drawn out to meet the windows.
The North Chapel is called the Morning Chapel, from its original use for morning prayer on weekdays. The mosaic above the altar is in imitation of a fresco by Raphael. That at the west end, by Salviati, is in memory of William Hale Hale, a voluminous writer and editor of the "Domesday of St. Paul's," who was a Residentiary, Archdeacon of London and Master of the Charterhouse. He died in 1870. The stained-glass window is in memory of the metaphysician, Henry Longueville Mansell, Dean of the Cathedral, who died suddenly, after a rule of three years, in 1871. It is by Hardman, and represents the Risen Christ and St. Thomas.
THE GEOMETRICAL STAIRCASE.[ToList]