As every collector of rare books and documents knows, one of the biggest barriers to collecting is preservation. The effect of time, dust, light, and moisture in the environment on paper and parchment can often lead to discoloration and degradation. Care must be taken to protect delicate books and documents from being slowly destroyed by age and the elements.
This is no different for historical documents, whose caretakers endure great pains to preserve history's most important works. In the case of the Constitution of the United States, the National Archive enlisted an unlikely source to help preserve one of America's most notable documents: NASA.
The Constitution of the United States was penned in 1787 and signed by seventeen of the most important figures in government at the time, including Benjamin Franklin, Thomas Jefferson, Alexander Hamilton, and George Washington. The Constitution has been housed at their permanent home in the National Archive in Washington, DC.
The Constitution only left the archive for a temporary stay at Fort Knox after the bombing of Pearl Harbor during World War II. Since 1953, all four pages of the Constitution have been on display in the Rotunda of the Charters of Freedom, which is also home to the Declaration of Independence and the Bill of Rights.
Archivists placed the document in a sealed glass encasement filled with inert helium gas to prepare the Constitution for display. The intention was for the helium to create a safe atmosphere in which the pages would be protected from damage from chemical corrosion from the air. This process impacts all objects, particularly parchment, over time. However, as the years passed, archivists noticed white splotches appearing on the Constitution. They had to figure out what the splotches were and how to prevent more from spreading over this important piece of American history, and they had to do it without opening the case, which would have created more opportunities for risky exposure to the elements. They called upon America's foremost atmospheric scientists to do this: NASA.
Using laser spectroscopy, NASA determined that the inert helium had not broken down and was still present inside the case, meaning that initial fears that it had degraded, leaving the parchment entirely unprotected, was not a concern. However, they did determine that the humidity in the case was nearly twice what it should have been to offer the Constitution optimum protection. As a result, water vapor was absorbed by the backing material of the Constitution, meaning the document itself was resting on something far too damp to offer it protection. The dampness could not escape the box or the backing and slowly damaged the Constitution. The white spots on the parchment were chemicals from the glass that were leaching out of it due to the high amount of water vapor within the case.
Armed with this information, the National Archive created a new case for the Constitution in 2003, utilizing advancements made in document preservation. This new case made of titanium utilizes inert argon gas rather than helium, making it much more humidity-resistant. This ensures that ink will not flake off and that no more splotches form on the parchment. Thanks to the hard work of the archivists and preservation specialists at the National Archive and NASA, this important piece of history will be preserved for years.
