SUSPENSION BRIDGES/ l93 



there are several; the chief of which are that at Newbury-port, over the 

 Merrinack, which is a curve whose cord measures 244 feet a second, 

 over the Brandywine, at Wilmington, of 145ft. a third, at Brownsville, 

 which measures 120 feet from point to point of suspension, and another 

 close by, which has an inverted suspended arch of 112 feet cord Tb,F 

 most remarkable in England is 



THE MENAI BRIDGE. 



In 1818, the late Mr. Telford was employed by the then Government, 

 to make surveys for the much needed improvements of the Holyhead 

 road, to Ireland. Between Bangor and Holyhead, and dividing the 

 main land from the Isle of Anglesea, where the latter is situate, there 

 is a strait, or arm of the sea, called Menai Straits, through which the" 

 tide flows with great velocity, and, from local circumstances, in a very 

 peculiar manner. Previous to 1818, the passage across the straits was 

 accomplished by means of Ferry Boats ; these, exclusive of the delay of 

 transit (no ordinary consideration, by the way, in the immense traffic with 

 the Irish capital) was very frequently attended with great danger. To 

 remedy this evil, Mr Telford suggested the erection of a suspension 

 bridge. The obstacles to be overcome, were a rapid stream, with high 

 banks : to have erected a bridge of the usual construction would have 

 obstructed the navigation ; besides, too, the erection of piers in the bed of 

 the sea was impracticable, and the advantage of obtaining direct com- 

 munication with the Sister Kingdom was of the highest importance. 



This bridge is partly of stone and partly of iron, and consists of seven 

 stone arches, exceeding in magnitude every work of the kind in the world. 

 They connect the land with the two main piers, which rise 53 feet aboVe 

 the level of the road, over the top of which the chains are suspended, 

 each chain being 1714 feet from the fastening in the rock ; the road way 

 is 100 feet above the surface of the water, at high tide ; the opening 

 between the points of suspension is 560 feet; the platform is about 

 30 feet in ( breadth. The whole is suspended from four lines of strong iron 

 cables, by perpendicular iron rods, five feet apart; the cables pass over 

 rollers on the top of pillars, and are fixed to iron frames under ground, 

 which are kept down by masonry; the suspending power of the chains is 

 calculated at 2016 tons, the total weight of each chain is 121 tons, and 

 the weight of the bridge between the points of suspension, is 489 tons. 

 It is said, that " the top masts of the first three-masted vessel which had 

 passed under the bridge, were nearly as high as those of a frigate, but 

 they cleared 12^ feet below the level of the roadway." As we before 



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