• Sara Thompson

Oak Gall Ink Integral to Independence


Declaration of Independence
Declaration of Independence

By Sara Thompson

Special to the Enterprise


Independence Day is often filled with food, fun, and friends. Celebrations can include grilling food, fun desserts, playing games or watching movies, and just spending time with our loved ones. The wording of the Declaration of Independence was approved and ratified on July 4th, 1776. The original document, including changes, is housed in the Library of Congress, with the official document that was signed being on display at the National Archives.


Several of the drafts of the Declaration were likely written on hemp paper, with the official document being written on parchment. Parchment was made from treated animal skin, usually sheepskin, that makes a thin, but durable writing surface. The ink used for the Declaration, Constitution, Bill of Rights, and most official documents of the time was oak gall ink, also known as iron gall ink.


Oak gall ink has been widely used since the 5th century and is still produced today for hobbyists. The ink is relatively easy to make, needing only a few specific ingredients. Oak galls are formed when a gall wasp female lays her eggs in new growth on an oak tree. The tree reacts to a chemical also injected by the wasp to envelop the eggs in a hard, ball-like mass. These galls fall from the tree and the wasp larva eat their way out leaving the mass behind to decompose naturally. When crushed and soaked in water, oak galls create a dark brown liquid that forms the base of the ink. After straining the liquid, it is mixed with iron sulfate to give it a darker color, and gum arabic which is a binder. The resulting liquid is oak gall ink, and is one of the longest lasting inks, which is why it has been used for centuries.


The combination of using durable parchment, and a well-known lasting ink like oak gall ink helps give documents, such as the Declaration of Independence, a good chance of avoiding fading and deterioration. Efforts to preserve the document in a controlled environment also makes it so this important document can be viewed for generations to come. We hope that everyone has a fun and safe Independence Day this year.



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