I wonder how many people viewing George's beautiful photograph know or care that the suspension bridge in the background is the prototype for John Robeling's more famous New York bridge, and many more through out our world. All suspension bridges are working machines in that the deck spans expand and contract in length as the structure heats up or cools down. Likewise the suspension cables also lengthen as the structure heats and shorten as the structure cools. The life of a suspension bridge is totally dependent upon how well it is protected from moisture and rusting. Protecting the main linear cables is critical, the vertical cables can be replaced easily if needed. The structural steel components also need painting on a scheduled basis. Suspension bridges really are "Live" as they are in continuous motion at all times.
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