FURMANFILMS of one continuous wire, although they are spun two at a time. The final bundle of each cable had over 17,000 strands in it! Each of these big spools holds 57 miles of wire. The bridge used 1500 of them to make the cables. If you look at the center of the wheel, you can see a cowbell. Thats the not so sophisticated, but an effective way that people knew the wheel was coming...nobody get hurt. When one spool of wire was empty, it was joined to the next drum by a threaded sieve. This allowed the wire to be continuous, with no loss of strength. As the cable would go by, workers placed it with the others in its strand. When one spool was finished, they would take out shims that had been placed in the cable, to adjust the tension. But one morning the sun came up very hot on the Oakland side, just as a sudden cold spell blew in from the Golden Gate. The expansion caused the wire to pull off one of the shoes holding it. It sounded like a missle going off as it whipped back and forth across the span. Fortunately, nobody was seriously hurt, but all the 472 wires in that strand had come loose, had to be taken out and the whole strand re-spun. They dumped the unusable strand of cable in the bay, but (new narr) after it kept comming up on the merchant ships anchors, the American Bridge Company had to dive down and haul it out of the bay. There is a total of 70,000 miles of wire in the cables of 34