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Mount Rushmore, Measurement of

Mount Rushmore, Measurement of


The Mount Rushmore National Memorial is one of the world's largest sculptural and engineering projects. Sculptor-designer John Gutzon de la Mothe Borglum (18671941) was contracted in 1927 to carve the solid-granite memorial. Borglum conceived the model figures, brought them to life within the mountain's stone, and directed 400 artisans until his death in 1941. Later that year, his son Lincoln finished the project, which had spanned 14 years (6.5 years of actual carving and 8.5 years of delays due to lack of money and bad weather) at a cost of $1 million.

Mount Rushmore is considered a priceless U.S. treasure, memorializing the first 150 years of the country's struggle for independence and the birth of the republic as represented by George Washington; the idea of representative government in an expanding nation as envisioned by Thomas Jefferson; the preservation of the union of states and the equality for all citizens as championed by Abraham Lincoln; and the twentieth-century developmental role of the United States in world affairs and economy as promoted by Theodore Roosevelt.

Mount Rushmore would not have been possible without Borglum's earlier carving experience of Confederate leaders on Stone Mountain. In the Rushmore project, Borglum employed few conventional sculpturing methods

in what was a unique engineering accomplishment. Borglum knew that he needed a cliff 400- to 500-feet in height; it had to lay at an angle so the main wall would face toward the sun; and there had to be sufficient amounts of even, unblemished stone to provide an acre of upright surface.

The presidential models were based on descriptions, paintings, photographs, life masks, and Borglum's interpretations. Initially, Borglum climbed down the mountain to locate Washington's nose line, eyebrows, and chin, marking each with red paint. From these points, he studied and mathematically calculated the scale necessary for the first head. Realizing the importance of models at the worksite, Borglum displayed a five-foot mask of each figure as a guide for the workers. However, Borglum did not simply transpose the models directly onto the granite; rather he fine-tuned the heads into artwork. In fact, Borglum realized that to transfer accurately his models into finished heads, he needed mathematical and engineering concepts. What he had to be, besides a sculptor, was an explosives expert, a geologist, a miner, an engineer, and a mathematician.

Scale in Mount Rushmore

Borglum constructed a "pointing machine" that enabled the transfer of mathematical dimensions of his models onto the mountain with a simple ratio of 1:12. That is, 1 inch on the model equaled 12 inches (1 foot) on the mountain. Each model was measured the same way (as shown in the diagram below). A metal shaft (1) was placed upright at the center of the top of the head, the "master point." A protractor (2), in degrees, was attached at the shaft's base. A horizontal bar (3) was placed on the protractor's central axis and pivoted to measure right and left angles from the centerline of the model's face. A weighted plumb-bob (4) was dropped from the horizontal bar and slid back and forth to measure the horizontal distance from the master point to the position on the bar where the plumb-bob touched a head-point being measured. The plumb-bob was also raised or lowered to measure the vertical distance from the bar on the top of the head to that particular head-point.

Each reference point on the model received three measurements: (a) a rotational (angular) measurement along the protractor, (b) a horizontal distance (linear) measurement along the bar, and (c) a vertical distance (linear) measurement along the plumb-bob. The two linear measurements for each reference point were multiplied by 12, with the angular measurement remaining constant, and then transferred to the mountain with a large-scale "Rushmore pointing machine."

This machine was secured at the mountaintop with a vertical mast, horizontal steel boom, and steel-slab protractor. Borglum used it in this way: If the model measure from the top of Washington's wig to his nose measured 20 inches, that length was multiplied by 12 to find that his nose on Rushmore measured 240 inches, or 20 feet, from the top of his head. However, the angular measurement remains the same between the model and the mountain since the definition of an angle is the ratio of a circle's arc length (s ) and its radius (r ), and that ratio remains constant for both model and mountain. That is, if the model ratio of arc length to radius is , then the mountain ratio of arc length to radius is , and the 12s cancel each other out. This system of transferring measurements from small to large pointing machines proved to be so effective that it was the only necessary measuring system.

Carving Mount Rushmore

An oval-shaped volume was first dynamited to remove sheets of excess stone for each roughened head. This "egg" was divided into three sectionsone at the eyebrow line, another at the nose end, and a third at the chin end. Rough shaping of heads began as the surface was removed with smaller charges of dynamite until good carving stone was reached. After a reference point, such as a nose tip, was located, lines of holes were drilled from 2 to 6 feet deep. Excess rock was removed with mini-charges of dynamite (sometimes only a half ounce) inserted into the holes, sometimes within inches of the finished surface.

Drillers suspended over the mountain's face by cables in swing seats then shaped the features. Pneumatic drills punctured the surface with a honeycomb series of holes at intervals of about 3 inches. The holes' depths ultimately shaped the finished "skin." The remaining rock was later chiseled with a drill, or a hammer and wedging tool, to the finished depth. Finally, the surface was smoothed with pneumatic hammers in a process called bumping to create a white surface as smooth as a concrete sidewalk. Measuring-drilling-blasting-drilling-wedging-bumping became the work cycle as 450,000 tons of rocks were removed.

The work on Mount Rushmore was Borglum's way to preserve a symbol of a great national ideal. Borglum never felt anyone (including himself) was endowed at birth with superior talents. His ability as a successful artist was due to trained observation, hard work, and the ability to use engineering and mathematical methods to produce his artistic creations, including the impressive Mount Rushmore.

see also Ratio, Rate and Proportion; Scale Drawings and Models.

William Arthur Atkins and

Philip Edward Koth

Bibliography

Casey, Robert J., and Mary Borglum. Give the Man Room: The Story of Gutzon Borglum. Indianapolis: Bobbs-Merrill, 1952.

Fite, Gilbert C. Mount Rushmore. Norman, OK: University of Oklahoma Press, 1952.

Shaff, Howard, and Audrey Karl Shaff. Six Wars at a Time: The Life and Times of Gutzon Borglum, Sculptor of Mount Rushmore. Sioux Falls, SD: Center for Western Studies, Augustana College, 1985.

Smith, Rex Allen. The Carving of Mount Rushmore. New York: Abbeville Press, 1985.

Internet Resources

"The Borglum Era 19161925" and "Gutzon Borglum." The University of Virginia: American Studies. <http://xroads.virginia.edu/~UG97/stone/timeln2.html> and <http://xroads.virginia.edu/~UG97/stone/gutzon.html>.

"Mount Rushmore." South Dakota travelsd.com. South Dakota Department of Tourism. <http://www.travelsd.com/parks/rushmore/index.htm>.

"Mount Rushmore History: The Making of Mount Rushmore." American Park Network. <http://www.americanparknetwork.com/parkinfo/ru/history/carve.html>.


MOUNT RUSHMORE'S NEIGHBOR

Another monumental sculpture is taking shape in the hard rock of the Black Hills. Honoring Native American Chief Crazy Horse, the work depicts the warrior on horseback. The sculpture was begun in 1947 by Korczak Ziolkowski, who had assisted Borglum on Mount Rushmore. A celebration was held in 1998 when the chief's face (measuring nine stories high) was completed.

When the entire work is finished, the tribute is slated to be the largest sculpture in the world, standing more than 560-feet high and 640-feet long. Ziolkowski, who died in 1982, took steps to ensure that his vision could be completed by other carvers, leaving detailed plans and specifications for others to follow.


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Mount Rushmore

MOUNT RUSHMORE

MOUNT RUSHMORE is the world's largest sculpture and foremost mountain carving. Located about twenty-five miles southwest of Rapid City, South Dakota, in the Black Hills National Forest, the memorial commemorates the foundation, preservation, and expansion of the United States and features the faces of four of the nation's most famous presidents, George Washington, Thomas Jefferson, Abraham Lincoln, and Theodore Roosevelt. Each of the sculpted faces is over sixty feet high. Carved out of a granite cliff atop the 5,725-foot-high mountain, the memorial is visible from miles away.

In 1923 the South Dakota state historian Doane Robinson initially proposed a memorial of giant sculptures in the Black Hills as a way to commemorate heroes of the old West, like the explorers Meriwether Lewis and William Clark and the Sioux Indian leader Red Cloud. Robinson understood that, in the era of the beginnings of widespread automobile ownership and the development of a vacation industry in America, such a monument would attract tourists and bring extra revenue to the region. He contacted the sculptor Gutzon Borglum, who was then famous for his work on a Confederate memorial at Stone Mountain in Georgia. Borglum traveled to South Dakota in 1924 and endorsed the project but introduced


a fundamental change in its scope. Rather than a western memorial of regional interest, the fiercely patriotic Borglum envisioned a memorial national in character that would appeal to all Americans. In fact, Borglum suggested the memorial feature carvings of the four presidents. After surveying the Black Hills for a suitable cliff in 1925, Borglum chose Mount Rushmore, and carving began in 1927.

Fourteen years later, in October 1941, work at Mount Rushmore finally came to an end, though less than half that time was actually spent on carving and sculpting the monument. Lack of money for the project was a constant problem, which often shut down operations for whole seasons at a time. The fact that Mount Rushmore was meant as a national memorial did help, however. South Dakota senator Peter Norbeck and Borglum himself often successfully lobbied Congress for funds, even during the Great Depression. Of the nearly $1 million total cost of carving Mount Rushmore, more than $800,000 came from federal sources.

In 1933, President Franklin Roosevelt placed the project under the jurisdiction of the National Park Service, which continued to administer the memorial. "The Shrine to Democracy," as Mount Rushmore National Memorial is often called, is visited by more than 2.6 million sightseers annually, fulfilling both Robinson's dream of a historical tourist attraction in the Black Hills and Borglum's vision of a lasting monument to America's majesty.

BIBLIOGRAPHY

Price, Willadene. Gutzon Borglum, Artist and Patriot. Chicago: Rand, 1961.

Smith, Rex Alan. The Carving of Mount Rushmore. New York: Abbeville Press, 1985.

NoahGelfand

See alsoArt: Sculpture ; National Park System .

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Mount Rushmore National Memorial

Mount Rushmore National Memorial, 1,278 acres (518 hectares), SW S.Dak., in the Black Hills; est. 1925, dedicated 1927. There, carved on the face of the mountain and visible for 60 mi (97 km), are the enormous (60 ft/18.3 m high) heads of four U.S. presidents—Washington, Jefferson, Lincoln, and Theodore Roosevelt. The sculpture was designed by Gutzon Borglum, who had even more ambitious plans for the site. These were abandoned when he died (1941), and the work was finished later that year by his son Lincoln. In all, it took 14 years to complete the figures, which during the summer are visited by more than 20,000 tourists daily. See National Parks and Monuments, table.

See J. Taliaferro, Great White Fathers: The Story of the Obsessive Quest to Create Mount Rushmore (2002).

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Mount Rushmore

Mount Rushmore Mountain in the Black Hills, sw South Dakota, USA. From 1927 Gutzon Borglum carved out the colossal busts of US Presidents Washington, Jefferson, Lincoln, and Theodore Roosevelt from the granite face of Mount Rushmore. After Gutzon's death in 1941, his son completed the work. Area: 5sq km (2sq mi).

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Rushmore, Mount

Rushmore, Mount a mountain in the Black Hills of South Dakota, noted for its giant busts of four US Presidents— George Washington, Thomas Jefferson, Abraham Lincoln, and Theodore Roosevelt—carved (1927–41) under the direction of the sculptor Gutzon Borglum (1867–1941).

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Rushmore, Mount

Mount Rushmore: see Mount Rushmore National Memorial.

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