A detail section of John A. Roebling's patented continuous cable strand, a trademark of his suspension bridges.
A detail section of John A
A cable was comprised of many smaller strands of oiled wrought iron bundled together multiple times, wrapped with more and then varnished or painted for weathering ability. Each 8-1/2-inch diameter suspension cable is made of 2,150 individual wires bundled together into 7 strands, "spun" into a continuous strand across the Delaware River between stone piers. Each 576-foot cable was varnished and bound by a continuous wrapping of iron wire to protect it from the weather.