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WILLIAM KDWAHDS, BRIDGE BUILDER. PAKT IV. 



adopted of more equally balancing the work and relieving 

 the severe thrust upon the haunches, was to introduce 

 three cylindrical holes or tunnels in the masonry at that 

 part of the bridge. The same plan is found to have 

 been adopted in some of the ancient bridges, and Perronet, 

 the great French engineer, not only formed such tunnels 

 over the haunches, but occasionally in the piers them- 

 selves. Where Edwards gained his information as to 

 the expedient, or whether he had gathered it from his 

 own bitter experience, is not known; but it answered 



PONT-Y-PRYDD. [By Percival Skelton.j 



his purpose. Three cylindrical holes w r ere built over 

 each haunch the lowest and outermost nine feet in 

 diameter, the next six feet, and the highest and inner- 

 most three feet. The arch, the same in width as tliat 

 which fell four years before, was finished in 1755, and 



