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pending rods nor bearers for the platformof the road; that resting upon the chain-bars. 2d, He proposed to continue chain-bridges to the shores from the props, in-stead of erecting arches from them; forchain-bars must be continued of the sametension to the shores to resist the hori-zontal drawing as ties, and therefore theymay as well be used also for bearers. 3d,His bridge is not required to be so widefor the same thoroughfare, nor the propsrequired to be so high; for if there be only16 cables in the proposed bridge (instead of50 which the author deduces to be required),each occupying a space of 4 inches, theremust be a space of 5 feet 4 inches occupiedwhere there cannot be any thoroughfare,and, of course, the smaller the angles at thepoints of suspension the lower the props.

Having now investigated the mannerof the construction of the Menai bridge, asrecommended by the Committee of theHouse of Commons , as well by referenceto a natural pendent bridge, as by calcu-lation from principles derived from it; itremains now to forget the questions which

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