How science helped—and harmed—efforts to preserve the U.S.’s founding documents.
The official declaration of America’s independence from Britain may be dated July 4, 1776, but the story of the Thomas Jefferson’s hallowed document really begins two weeks later. On July 19, the Continental Congress ordered a scribe, Pennsylvania State House clerk Timothy Matlack, to write the words on a piece of parchment big enough for everyone to read—and with room for signatures.
Since then, the Declaration of Independence has had a fairly rough time. A forensic analysis of the document shows some rough handling, damaging displays, and even a mysterious handprint. Understanding why it looks the way that it does — much more faded and battered than the U.S. Constitution or The Bill of Rights — is a romp through the history of printing, preservation, and patriotism.
Old Tools, Faded Inks, Unfortunate Folds
The story starts with Matlack’s tools—a quill dipped in iron gall ink. That kind of ink was nothing special. It was cheap and commonly available at the time. “Because of its indelibility, it was the ink of choice for documentation from the Middle Ages to the twentieth century”—so says a non-profit website dedicated to iron gall ink.
Its ingredients are stated in the name. Ground gall nuts, taken from an oak-like tree, were boiled to draw out tannic acid, which was mixed with iron sulfate scraped from nails. “The ingredients could also be mixed dry, which would produce ink the moment water was added to it,” the website continues. “This powder would make for a perfect traveling ink, created only as needed to avoid the opportunity for mold growth.” The scribe would etch letters that would gradually darken as oxygen works on the iron. Over time, that dark color mellows to a soft brown.
But the current custodians of the document—the National Archives—will tell you that almost no original ink remains on the Declaration of Independence. The document had no permanent home during the earliest days of the Revolutionary War, resulting in crude folding and rolling, causing some of the ink to flake off. As you can imagine, this rough treatment led to permanent damage.
“Evidence of previous folding and rolling is still visible on the Declaration,” says one National Archives analysis. “Two primary vertical fold lines run from top to bottom, and there are numerous horizontal fold lines especially in the lower part of the document.”
Good Intentions, Terrible Results
Restorers with the best of intentions can still do plenty of harm, and early efforts to protect the Declaration damaged the document further.
While Secretary of State, future president John Quincy Adams commissioned full-sized copies of the Declaration to be made to limit the exposure of the original. The resulting copperplate is dated July 4, 1823.
It was a good idea, but the method of the day involved engraving the image on a copperplate. Step one of this involved pressing wet fabric against the ink to transfer an exact copy of the words onto the plate. This removed some ink and accounts for some of the faded look we see today, especially around the signatures.
Then things went from bad to worse. In 1841, the first exhibition hall in Washington D.C. opened in the Patent Office Building (now the National Portrait Gallery), and what better thing to display than the Declaration of Independence? It sounded like a smart idea, but over the course of 35 years on display, the document was exposed to damaging light that further faded what little ink remained.
Read more: https://www.popularmechanics.com/technology/a22025447/declaration-of-independence-science/