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While TechTV is currently down, please enjoy our letterlocking videos on Vimeo: Please enjoy this growing collection of instructional videos showcasing the history and technology of document security and letter writing. Many of the videos show how historic letters or documents were once folded and secured to function as their own enclosures or sending devices before and after the invention of the gummed envelope. We call this letterlocking. Letterlocking is part of a 10,000 year-old information security tradition, ranging from Mesopotamian clay bullae to Bitcoin. Artists, businessman, literary authors, regents, secretaries, scientists, spymasters, and the general public wrote and locked their letters shut. Veneto businessman Tomaso di Livrieri, Elizabeth I, Queen of England, poet and preacher John Donne, and sometime Queen of Bohemia Elizabeth Stuart used more than one letterlocking format; some formats had more built-in security than others. The formats may have correlated to the sensitivity of the information contained inside. We learn about the different formats by creating detailed models of the original historic manuscripts and we thank the many institutions that granted us direct access to their treasures (the British Library, the Houghton Library, Harvard University, the Folger Shakespeare Library, the Koninklijke Bibliotheek, the Vatican Secret Archives, and many others). We can only perform historic letterlocking research with direct access to original manuscripts. Documenting the physical details of well-preserved originals has helped to define the different locking formats with their multiple levels of built-in security and their various authentication devices. Making models of historic originals help us understand how now “opened” letters once functioned as three-dimensional “closed” objects. Understanding the minute physical details on the historic locked letters enable conservators and scholars in allied disciplines to define formats while preserving the integrity of the originals so that the information is available for access and interpretation. Letters are a fundamental format of private and public record keeping. They may be gathered into bundles, tucked around something, or compiled into bound structures to keep related materials together. Letterlocked documents are part of a larger study of archival filing and storing systems; they are one of 250 legal and accounting documents and bound record formats found in well-preserved holdings similar to the Fondo Veneto Sezione II in the Vatican Secret Archives. (For example, see videos showing one of the book structures called a "filza" on YouTube. Video titles are: "Filza-simple filing system 1660s Italian" and "Filza. Filing system with tie and lace point 1660s Italian"). The letter is the artifact, the witness to a specific historic moment. Alter its physical evidence and the witness loses its voice. Many thanks to Academic Media Production Services for producing the videos, to the MIT Libraries, and to colleagues Dr. Nadine Akkerman (University of Leiden) and Dr. Daniel Smith (Lincoln College, University of Oxford) for collaborating with us. Notice: Letterlock responsibly. Be mindful of open flames or hot tools in the workspace. Jana Dambrogio. Thomas F. Peterson (1957) Conservator. Web: Twitter: @letterlocking #letterlocking

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