RENAISSANCE, THE, and its Genius, in the war-bridge at Würzburg, Bavaria, 259; in Venetian bridges, 211-12, 307, 315-16; in the bastille bridge at Châtellerault, 331-4; in the gradual decline of bridges from military forethought into a complete disregard for national defence, 336-44; in wasteful artistry such as redundant ornament and too elaborate parapets, 320, 321, 322, 324, 325, 326. RENNIE, GEORGE, his design for London New Bridge has defects of scale, 256, 257. RENNIE, JOHN, _b._ 1761--d. 1821, his poor bridge over the Thames at Southwark was financed by a Company, not by the City, as if London were a trivial village with some new industries that needed encouragement, 326-7. RENNIE, SIR JOHN, son of John Rennie and brother of George Rennie, was the acting engineer during the building of New London Bridge, according to Professor Fleeming Jenkin. RESEARCH, its illimitable scope in the study of bridges, 3-13. RHÔNE, THE RIVER, his two famous old bridges, the Pont St. Bénézet and the Pont St. Esprit, both constructed by the _Frères Pontifes_, or Pontist Brothers. See Brangwyn’s pictures and the text. RIALTO, Venice, 209, 211-12. RIBBED ARCHES, like those in the Monnow Bridge at Monmouth, 281, and the Pont de Vernay at Airvault, Deux-Sèvres, plate facing page 96. The introduction of ribbed vaulting into English churches and bridges, 93-100. Professor Moseley’s remarks on groined or ribbed arches may be quoted here from Hann and Hosking’s profuse volumes. “The groin ... is nothing more than an arch whose voussoirs vary as well in breadth as in depth. The centres of gravity of the different elementary voussoirs of this mass lie all in its plane of symmetry. Its line of resistance is therefore in that plane.... Four groins commonly spring from one abutment; each _opposite_ pair being addossed, and each _adjacent_ pair uniting their margins. Thus they lend one another mutual support, partake in the properties of a dome, and form a continued covering. The groined arch is of all arches the most stable; and could materials be found of sufficient strength to form its abutments and the parts about its springing, I am inclined to think that it might be built safely of any required degree of flatness, and that spaces of enormous dimensions might readily be covered by it.” Yet “modern builders, whilst they have erected the common arch on a scale of magnitude nearly approaching perhaps the limits to which it can be safely carried, have been remarkably timid in the use of the groin.” Progress may be compared to a dilatory army that ever fails to march forward with all its needed units. RICHMOND BRIDGE, Yorkshire, had a chapel, 231. RIMINI, her Roman bridges, 82, 199, 200, 220.