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cepted, in respect to many opinions, which mayappear erroneous in this tract.
By substituting ribs of the same curvature for thevarying elliptic ribs in a groined ribbed vault, themason again is reduced to the proper level of an han-dicraft, and the simplicity of construction may alsovie with that of the original cylindrical vault ; whilethe apparent intricacy has given rise to a story notless false and derogatory to the great man who is thesubject of it, than characteristic of the cheat thisdescription of vaulting practices even upon mindsmore than ordinarily informed, inquiring, and inge-nious. Mr. Walpole (Yol. I. p. 185. Anec. of Paint.)has related, without a remark on the fallaciousness ofthe story, that “ there is a tradition, that Sir Chris topher Wren went once a year to survey the roof ofthe Chapel of King’s College, Cambridge (Fig. 22.),and said, that if any man would show him where toplace the first stone, he would engage to build an-other.” In the contemplation of the distant objectsof antiquity, Mr. Walpole may be esteemed a glassof great power ; but Mr. Walpole, like other glasses,confuses objects that are not within his focus.
The dome which crowns or separates the periphe-ries of the inverted parts of these quadrants (Fig. 21.),and acts as a key-stone, has these practical advantagesover the pendent dome of St. Sophia, that, by beingcomposed of ribs and pannels, the parts might bemade of almost any lightness; and that the domeis independent of any assistance, except from thepiers on which it rests.
It will be observed, that the triangular spaces(Fig , 21.) concave to fit the convexities of the centraldome j and parts of the inverted quadrants must be level