io Book of Engineering 



bridge is 3,770 feet, and no less than 

 50,000 tons of steel have been employed in 

 the main structure. 



The two halves were built slowly out- 

 wards from either side and for six years 

 they were growing either in the form of 

 steel plates and girders in the making, or 

 in being placed in position, until, in 1930, 

 the connecting link was made in an arch 

 which had a span of 1,650 feet. The arch 

 rises to a height of 410 feet, and there is 

 always a headway of 170 feet at high water, 

 and considerably more at low tide, thus the 

 biggest steamship can enter without waiting 

 outside for the tide to fall. 



The bridge carries four lines of standard- 

 gauge railway, a roadway 57 feet wide, 

 with two footways each io feet wide. It 

 is estimated that the maximum capacity of 

 the bridge will be 168 electric trains, 6,000 

 vehicles, and 40,000 foot passengers an 

 hour remarkable figures these. The bridge 

 is due to be opened for traffic in 1932. 



The Romans probably built the first bridge 

 across the Tyne something like eighteen 



