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GOTHIC ARCHITECTURE
CHAP.
section (Fig. 36), taken at the level, a (Fig. 35), will more fully explain the form of this portion of the vault and the manner in which the pressures are gathered upon the pier.
FIG. 35.
Here a, b, and c are the great ribs whose thrusts, in the direction of the arrows, are concentrated upon the pier, d,and are counterbraced by the flying buttress, e. In other words, the section through the vaulting conoid at half its
