When the Mount Vernon Place Conservancy restored and rededicated the Washington Monument last summer, excitement surrounding the opening drowned out news of one important new feature: state-of-the-art digital exhibits that allow visitors to view the national treasure, which had been closed since 2010, in a whole new way.
The exhibit’s handsome, large interactive touch tables let visitors navigate through the experience, with zooming capabilities and beautiful imagery. Two main components — a virtual tour of the monument and a richly illustrated historical timeline — tell the story of the monument like never before. The high-tech features can be found on the conservancy’s website.
Not only do the exhibits, developed by MFM exhibition designers and digital partner Cortina Productions, incorporate the latest innovations in museum design, they also include new facts about the monument only recently discovered thanks to digital scanning technology.
Take, for one, the height of the Washington Monument, which over the years has come into question. Depending on the source, over the past half century the monument’s height was variously given as anywhere between 170 feet to over 200 feet. In one early document, monument architect Robert Mills listed its completed height as 180 feet.
As part of the restoration plans for Mount Vernon Place, the entire area was scanned in 3-D by RK&K Engineers and the data compiled and manipulated by Direct Dimensions. They created 42 individual scans of Mount Vernon Place comprising 585 million data points creating a detailed “point cloud” of all the features and topography. The scans document that from the pavement, the monument is 178’ 8” tall, not too close to Mills’s original dimensions.
Considering that the monument’s fence and gates have never been altered and the height of the monument’s curb has not been changed, why is Mills’s dimension off by over a foot? The error contrasts sharply with his other dimensions, which are remarkably close to dimensions by modern scanning, including his dimension for the column proper — 120 feet –which is spot on.
“We think Mills’s may have miscalculated, and counted one area of the monument twice in his total measurements,” says Lance Humphries, chair of the conservancy’s restoration committee. The monument’s terrace parapet wall overlaps part of the base of the column–on Mills’s list he provided dimensions for both segments, but did not subtract the dimension of the overlapping section. “If we add his duplication to the current known established height–it is almost exactly 180 feet.”
Like the building’s height, the number of steps in the monument’s column has been changed over the years–or at least how they’ve been counted, since there is no evidence that the main run of marble steps has been altered. On Mills’s early list, he claimed there were 220 steps. Most modern sources list 228. “Mills may not have counted the eight landings (some, near the top, barely larger than steps) that occur at each of the staircase’s nine rotations,” says Humphries. During the restoration process, however, the steps were counted many times–it takes 227 steps to climb to the top. Previous generations may have included the starting point as a step.
The monument’s restoration scaffolding gave the project team unprecedented access to Enrico Causici’s colossal statue of Washington on the top of the monument. While the scaffold was up, the statue was 3-D laser scanned by Direct Dimensions using two different scanning technologies in only a few hours. Michael Raphael, CEO of Direct Dimensions observed: “Given the rare circumstance of this up-close access to the statue, and the importance of the Monument, we were pleased to offer our professional 3D services as pro bono to the Conservancy to accurately capture this important piece of history.”
The scan confirms that the statue, composed of three pieces, is 16’ 2” tall (Mills thought it was 16’ 6” feet). The amazing information that the 3-D scan provides — never available before — is the statue’s volume, since this can be calculated from the digital scan. Taking this volume–approximately 135 cubic feet–and a standard weight for a cubic foot of marble (168 pounds)–the weight of the statue can be determined for the first time in modern history: approximately 11 1/3 tons.
Mills, needing to understand the weight of the statue at the time he devised the derrick system used to raise the three pieces to the top in 1829, calculated the weight at between 15 and 16 ½ tons. “We are not sure how Mills came up with his weight for each piece of the sculpture, but he may have calculated based on the un-carved volume of each piece of stone, as he had no way to really determine how much volume remained after it was carved,” say Humphries. Fortunately for him, his calculations, therefore, erred on the heavy side–which did not compromise the integrity of his hoisting system. According to contemporary newspaper accounts, raising the statue’s three pieces went off without a hitch in November 1829, and the final piece was, amazingly, raised to the top in just over an hour.
With the 3-D scan of the statue, the conservancy has been able to include a fully rotational image of the statue in its digital exhibits. Considering the fidelity of the scan, it offers an up-close view of the statue impossible to the naked eye. With the scan data–which is just points of data, and not a photograph–Cortina Productions was able to add a marble texture to the data that very closely approximates the appearance of the actual statue.
Two hundred years years after the monument was begun, those who built it would be amazed at the opportunities technology offers to document and interpret the remarkable structure. Check it out in person or online.
All photographs courtesy Mount Vernon Place Conservancy, with the exception of Mill’s diary drawing courtesy Moise H. Goldstein Collection, Southeastern Architectural Archive, Special Collections Division, Tulane University Libraries.
Baltimore Fishbowl was a media sponsor for Monumental Bicentennial, the rededication and reopening of the Washington Monument.
