The Smithsonian's Birthday Bell
The Smithsonian's Birthday Bell
Architect James Renwick, Jr. designed the Smithsonian Building with a tall tower featuring four clock faces carved into the stone.
The Smithsonian's 150th Anniversary year presents an opportunity to fulfill the intent of the 1851 resolution. This 821-pound bronze bell was cast at the Whitechapel Bell Foundry, London, England. The foundry, which has been in continuous operation for 576 years, also cast Big Ben and the Liberty Bell.
The Smithsonian bell was cast on Sept. 21, 1995. It weighs 821 pounds and measures 34 inches in diameter. The metal is 77 percent copper and 23 percent tin. The inscription reads: For the increase and diffusion of knowledge; gift of the A.T. Cross Company to the Smithsonian Institution in our 150th year 1996. The inscribed bell also recognizes the donor, A.T. Cross Company, which shares the Smithsonian's year of origin, 1846. The bell will be lifted into its position on the clock tower roof, unseen from ground level, and will strike its' D-flat notes for the first time on the Smithsonian's birthday, August 10, 1996.
The bell is a stationary clock bell, and will be wired directly to the Castle tower clock. Electronic controls will regulate the bell's ringing and automatically adjust for daylight savings time. Smith of Derby Clockmakers, of Derby, England, is manufacturing the new clockworks for the Smithsonian bell.
The hour and minute hands currently on the clock faces will be replaced by new hands, also gilded, that will be more in keeping with the Castle's architecture. The tower's east-facing dial will also finally get its own set of hands to complete the four faces of the time-keeping clock tower.
Before the project was approved, the Smithsonian's Office of Design and Construction conducted a structural engineering assessment to ensure that the bell would have no negative impact on the building. Out of sight on top of the tower, the bell will be only audible to the public. A metal sheet under the bell will project its notes outward over the Mall, making its sounds nearly imperceptible to people inside the Castle.
At noon on Saturday, Aug. 10, 1996, the Smithsonian's 150th birthday, the bell will be hoisted to the Clock Tower on the North side of the Smithsonian Castle and connected to the clockwork there. It will be set to ring once an hour.
The Smithsonian Bell was made by the WhiteChapel Foundry. The Whitechapel Bell Foundry, which also creates ships' bells and handbells, is legendary in the field of bell-casting. It was chosen primarily because U.S. bellmakers no longer cast bells of this size, but also because of its history as maker of many of the most well-known public bells in use today, such as those of Big Ben, the Old Post Office and the Washington National Cathedral. Whitechapel also created the first Liberty Bell.
The bell casting process has remained virtually unchanged since medieval times: metal is heated to a molten state and poured into bell-shaped molds.
The construction of the mold is the first step in the process of bell casting. Composed of an outer "cope," and an inner core, the empty space left between the two parts is filled with molten metal.
The mold is built of bricks and loam (a mixture of clay, straw, goat's hair, and horse manure).
Both parts of the mold are smoothed and polished, then dried in an oven, coated with graphite, and clamped together. The mold is then ready to receive the molten metal.
The metal used in the casting of bronze bells is an alloy of 77% copper and 23% tin. Heated to 2140 degrees F (1171 degrees C), the molten metal is poured from the furnace into a massive ladle which is then brought to the mold on the overhead crane. The ladle is carefully tilted, discharging the liquid metal into the mold.
After a day of cooling, the mold is broken open to reveal the bell.
After all mold loam has been removed, the bell must then be tuned in order to produce a pleasing tone when struck. Tuning takes place on a vertical boring mill that works like a potter's wheel. While spinning upside down on the mill, metal is cut from the bell's interior until the desired tone is achieved.
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