About UH numbers
Explore a growing list of letters we've studied from more than 70 archives worldwide. We have cataloged over 7,000 letters and historical items related to letterlocking and document security.
This online inventory of UH numbers serves as a prototype for our online catalog, which will ultimately feature all 7,000 items.
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If you’re exploring the dictionary and want to head back,
Why study items from our Unlocking History Research Group archive?
Visiting an archive allows you to see the original letters we've examined, often displayed flat or refolded. Our archive offers a unique perspective on how these letters operated as three-dimensional objects, enhancing your understanding of their significance.
How to use the UH inventory list
You'll find underlined UH numbers that link to detailed technical information and downloadable resources, including images, articles, and foldable computational unfolding code—everything you need to deepen your study and appreciation of these historical artifacts!
UH#s & LUV#s
UH number is a four-digit number (UH####) and
LUV number is a three-digit number (LUV###).
Found in our resources, we refer to letters by UH# and videos of them by LUV#. Here, you will see letters arranged by UH# for ease of reference, with full citation details and access to freely available resources and technical information for the letter. We also give citation details for our models of that letter if they are stored in the Unlocking History Research Group archive in the Department of Distinctive Collections at MIT Libraries. In addition, we supply citation details for instructional videos of that letter, if any exist.
Unlocking History Research Group archive at MIT Libraries, MC0760
Our models of letters, and some original letters, are held in the Unlocking History Research Group archive at MIT Libraries, in a series of boxes numbered 1 to 52. The short form for this collection, used through this list of sources, is “MIT, MC0760,” followed by the box number.
The Brienne Collection
Sound and Vision The Hague catalogs the Brienne Collection as “I 46.” Letters within the collection are marked “DB” (an abbreviation of “De Brienne”), followed by a unique four-digit number. Hence, a full inventory number would be “I 46: DB-XXXX,” but in our book, this has been abbreviated to “DB-XXXX.”
Worth noting about LUV#s & UH#s
It is worth noting that not every UH# matches the corresponding LUV#. The first 250 LUV#s match their UH#s, but after that, the numbers diverge, so UH6107 (Pagu nonagon, 2017) is matched to LUV277. Some letters do not have matching instructional videos at all. For example, UH0277 (John Donne to Sir Henry Marten) has no corresponding LUV#.
Key to contributing authors of our videos
Contributing authors of our videos are signaled with the following initials:
AG = Amanda Ghassaei
AL = Ayako Letizia
BB = Brien Beidler
DSS = Daniel Starza Smith
EHC = Emily Hishta Cohen
HK = Hedi Kyle
HJ = Holly Jackson
JD = Jana Dambrogio
JP = Jennifer Pellecchia
LH = Lucas Haasis
LE = Linda Evans
LM = Leslie Morris
LMS = Lucy May Schofield
NA = Nadine Akkerman
NiA = Nicole Araya
RA = Rufeida Alhatimy
RV = Ruben Verwaal
SW = Sheree Watson, MD
SSU = The Signed, Sealed, and Undelivered team
TC = Tracy Chang
TL = Teresa Leone
UHRG = Unlocking History Research Group
UW = Ulla Warchol
WE = Walter O. Evans,