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The San Francisco Ferry Building Clock

Ferry Building Guides were recently treated to a talk by Dorian Clair, a specialist in antique clocks who in 2000 began working on the Ferry Building’s famous timepiece. Today the Ferry Building still boasts its original Special #4 clock made by the Boston clock maker E. Howard in 1898. It is the largest dialed, wind-up, mechanical clock in the world.

Before the ’06 quake, this top-of-the-line clock lost only two seconds a week. Although the clock is now powered by an electric motor installed by Dorian, the old weight and pendulum system is still in place and could be hooked up in a few hours. This system’s one-ton weight, which dropped 48 feet in 8 days when it powered the clock, now rests just above the main entrance. The Standard Clock Company added a slave drive system that ran the clock between 1918 and 1974, when the first electric motor was installed.

The clock is on the 9th floor of a 17-story tower; interestingly, the tower above the clock is of wood and stucco construction, with the upper columns made of wood covered in metal. Dorian told Guides that the tower was rather wobbly when he began his work in 2000, but was stabilized during the Ferry Building renovation. Originally the tower served as a ventilation system and as a result all the smoke from the ferries was drawn up to the clock, making it quite dirty when Dorian started his work in 2000.

The clock’s hands are 23 feet 2 inches in length, a bit smaller than Big Ben’s, and are made of layers of plywood that are screwed and glued together and covered with ten coats of epoxy paint. All four faces are driven by the same mechanism, but be aware as you are rushing to meet a tour that there is a two-minute play in the hands due to the wind. One of the old hands is on display in the Ferry Building’s main entranceway.

The chimes, a CD copy of Big Ben’s, are run by a computer located near the Commission’s Conference Room. In addition, music can be generated from a keyboard connected to this computer. Alert observers may have noted that occasionally the time and the chimes do not jibe. There are 11 horn speakers that are driven by a 1200 watt amplifier and are located just above the clock dials. The old 60 hp siren has been replaced by a smaller version that is heard every Tuesday at noon.

Nowadays Dorian maintains the clock three times a year. Early in the morning of October 31st, as the West “fell back” to Pacific Standard Time, City Guide Linda Dodge reports watching through binoculars as Dorian ran the clock backwards for an hour.

Photos reprinted with permission, San Francisco History Center, San Francisco Public Library

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Repainting the Clock Face in 1938

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Inside the Clockworks in 1950

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