158 The Menai Bridge near Bangor^ Carnarvonshire. 



and also two preventive capstans, commenced working, each 

 propelled by twenty-four men. To preserve an equanimity 

 [equability ?] in the rotatory evolutions of the two principal cap- 

 stans, a filer played several enlivening tunes, to keep the men re- 

 giUar in their steps; for wliich purpose they had been previously 

 trained. The chain rose majestically, and the gratifying sight 

 was enthusiastically enjoyed by each individual present. At fifty 

 muiutes after four o'clock, thejinal bolt was fixed, which com- 

 pleted the whole Ime of chain. From the casting off of the raft, 

 to the uniting of the chain, took up only two hours and twenty 

 minutes. 



This splendid specimen of British architecture will be a 

 lasting monument to the discernment of the present govern- 

 ment, for having called into requisition the transcendent talents 

 of Mr. Telford, who was present on the occasion. 



Upon the completion of the chain, three of the workmen 

 had the temerity to pass along the upper surface of the chain, 

 which forms an inverted curvature of 580 feet. The versed 

 sine of the arch is 43 feet. 



The following is a summary account of the dimensions of 

 the bridge : — The extreme length of the chain, from the fasten- 

 ings in the rocks, is about 1600 feet. The height of the road- 

 way from high-water line is 100 feet. Each of the seven small 

 piers, from high-water line to the spring of the arches, is 65 

 feet. The span of each arch is 52 feet. Each of the two sus- 

 pending piers is 52 feet above the road. The road on the 

 bridge consists of two carriage-ways, of 12 feet each, with a 

 footpath, of 4 feet, in the centre. The carriage-roads pass 

 through two arches, in the suspending piers, of the width of 

 9 feet, by 15 feet in height to the spring of the arches. To 

 counteract the contraction and expansion of the iron, from 

 the effect of the change of the temperature in winter and 

 summer, a set of rollers are placed under cast-iron saddles, 

 on the top of the suspending piers, where the chains rest. 

 The vertical rods, an inch square, suspended from the chains, 

 support the slippers for the flooring of the road-way, the rods 

 being placed 5 feet from each other. The chains, 16 in num- 

 ber, contain 5 bars each : length of the bar 9 feet 9 inches ; 

 width 3 inches by 1 inch square, with 6 connecting lengths at 

 each joint 1 foot 6 inches by 10 inches, and 1 inch square, 

 secured by two bolts at each joint, each bolt weighing about 

 fifty-six pounds. The total number of bars, in the cross sec- 

 tion of the chains, is eighty. 



A second chain was drawn over on Thursday morning, the 

 28th ; and there are fourteen other chains in readiness to 

 be drawn over when the tide will serve, which will complete 

 the line of suspension.— £c?2n. Joiirn. of Science. 



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