|Joe Dockrill posted|
bridge built outside a bridge, Niagara Falls, from suspension to steel span.................clever
- Buck, Richard (December 1898). "The Niagara Railway Arch". Transactions of the American Society of Civil Engineers 40 (836): Plate VIII. New York: American Society of Civil Engineers. [Wikipedia]
Bill Blake commented on his post
1897 - They build the new bridge around the structure of the old bridge.
|eBook, Digitized by Google, scrolled down several pages|
The suspension bridge being replaced is the second one built at this site. John A. Roebling built the first one between 1852 and 1855. I recognize the name because he was the first to manufacture wire rope in North America; and he built several suspensions bridges, including the Brooklyn Bridge, to expand the market for his wire. This was the first suspension bridge that carried a railroad. Many didn't thing a suspension bridge could carry a train because they were too flexible to carry the focused weight of a crossing train. The key was that John built a stiff, 18' deep double-deck truss. The upper level carried the tracks and the lower level was for carriage and pedestrian traffic. There were "four main cables 10 inches in diameter with 3,640 no. 9 gauge wires each." [StructureMag]
|Historic Photo from Frank Griggs Jr.|
|From the Niagara Falls Public Library [Public domain], via Wikimedia Commons|
|See page for author [Public domain], via Wikimedia Commons|
|1900 from Widipedia|
|bill Blake posted|
February 2018 - Nice photo of the Maple Leaf Express crossing the Whirlpool Suspension Bridge in Niagara Falls.