A series of ventilation tubes were installed up one leg of the Bay Bridge. The clear intent was to provide fresh air to workers above from the ground below. Here, the first two sections of tube were hung halfway up one leg and held in place with stout straps.

Close up of the installer working on a boom lift. Note that the man wore a safety harness. The yellow tubes were held up with what looked like boxing straps.

The next day started with a heavy rain storm that delayed work. Over the previous day the bottom half of the tubes had been installed all the way to the ground.

The rain slacked of mid day and allowed the work to continue. Dressed in rain gear and a safety harness, the man was flanked with two boxed tubes. It was unclear why it took two additional men on the ground to support one man in the air.

The worker operated the boom lift in a manner that allowed it to rise vertically with little horizontal drift. Notice how the previous day's straps caused partial collapse of one of the tubes.

The boom lift approached the place where the previous day's tubes began. Note the clouds just starting to clear in the distance.

The two men on the ground risked serious neck injury by craning their necks back to watch the man working high above.

Just as the tubes had been installed from the top down the day before, today's tubes would also be installed from the top down. The boom lift continued to rise slowly to the endpoint of the ventilation.

The two top tubes had already been installed. The worker had ascended a second time with a second load of two more tubes.

The rain returned as just a sprinkle but the work continued. The gap between the bottom and top tubes would still be finished this day.

The ends of the new tubes had been attached to the bottoms of the prior tubes. The worker made ready to descend, feeding out and strapping this next run of tubes.

Just like the gold spike joining the transcontinental railway, the top tubes were finally joined to the bottom tubes in the middle. Note the two men still waiting below and the lack of a crowd of well-wishers to cheer.

The worker attached the top tubes to the bottom tubes to finish this adventurous high-level part of the job.

The bottom of the tubes waited to be attached to the ventilation fan at the lower left.

On a Wednesday morning a month later, workers were being taken up to the bridge to begin work. To the left was the ventilation tube that was operating to bring fresh air to their workplace.

The typical image of a day's work above the Bay Bridge Maintenance Yard.

The ventilation tubes after a month of use. Notice the bases of the tubes are attached to stout ventilation machines. It was unclear if one sucked and one blew, or if they both blew.