Engineering Wonders of the World
Volume III

THE ADJUSTING TOGGLE USED FOR LOWERING THE CANTILEVERS OF THE RAILWAY ARCH BRIDGE, NIAGARA FALLS. (Photo, Pennsylvania Steel Company.) THE ARCH BRIDGES OF NIAGARA FALLS. This article describes two notable feats of Bridge Building, in which old Bridges have been replaced by new without disorganizing traffic. HE deep gorge below the Niagara Falls has afforded plentiful opportunity for the exercise of the bridge-builder’s art. Above the Falls the construction of a bridge is rendered impracticable by the width of the river and the strength of the current ; and as communication between the two banks was, and is, a matter of the utmost importance, advantage has been taken from time to time Successive Bridges across the Niagara Gorge. replaced in 1898 by another suspension bridge of modern design.) The third of thø series was the suspension bridge built in the years 1853-55 by Mr. J. A. Roebling to carry the trains of the Grand Trunk Railway. In its original form it had a wooden stiffening truss and masonry towers. The truss was replaced by one of of the comparative narrowness of the chasm through which the Niagara River flows after its great leap. In 1848 Mr. Charles Eilet erected the first dJ". yof the many bridges, one of the suspension /? , type, designed for light traffic only. Two . years later a suspension bridge of 1,040 feet span—the longest of its time—was added be- vy tween Queenston and Lewiston. (This was steel in 1880, and the masonry towers by steel towers in 1886, both operations being effected without disturbing the traffic. The fourth on the list is the suspension bridge of 1,268 feet span erected by Mr. Samuel Keefer in 18G8, between Niagara Falls and Clifton. It was too narrow to serve the purpose for which it was intended, and was widened in 1886 ; but three years later succumbed to the