Origami Heaven

A paperfolding paradise

The website of writer and paperfolding designer David Mitchell


Letterfolds and Letterlocks
This page attempts to record a summary of what is known about the origin and history of Letterfolds (although, at present, it is very much a work in progress). Please contact me if you know any of this information is incorrect or if you have any other information that should be added. Thank you.

Letterfolds are ways of folding letters so that they can be posted without the necessity for envelopes. Letterlocks are additional folds, often depending on cuts, which are used to lock the letterfold together in an attempt to make sure it can not be read in transit.

Historically the most usual way of folding a letter seems to have been to fold in both long edges, although not necessarily to the point where they would meet, to form a long, narrow rectangle, to fold one short edge of this rectangle inwards to create a pocket, then to fold the other short end inwards and tuck it inside the pocket to form a stable package. A wax seal can then be used to ensure the package will not come apart. I call this the basic rectangular letterfold.



A group of five almost complete letters written in the Sogdian language, each of which had been folded several times and bore the names of the sender and addressee on the outside, were found in 1907 by Sir Aurel Stein in Iran in a ruined watchtower on the Chinese frontier wall which formerly guarded the route between Tun-huang and Lou-lan. These documents are usually known as the Ancient Letters. They were once dated to within a few decades of the traditional date for the invention of paper in 105 A.D. and thus thought to be possibly the oldest paper documents in existence. Further consideration by scholars suggests that they are more correctly dated to the years 312-13.

Source: http://www.iranicaonline.org/articles/ancient-letters



The manuscript 'De Viribus Quantitatis' by Luca Pacioli which was written in or around 1502 gives a description of three ways to seal a letter without any wax.

a, 'Given a rectangular sheet of paper, one is to fold it widthwise so to obtain a strip of paper. Both ends of the paper are bent in such a way to obtain a similar trapeze standing out to each side of the strip. The side of the trapeze gives the next fold, which is to be folded over until both ends are close enough that after folding them into each other they form a square shape.'

This sounds similar to the Love Knot Letterfold but with the ends tucked in to form a square.

b, 'The second method is by far simpler. Start with a square paper. Fold it diagonally. Next, tuck one of the acute angled tips of the triangle formed into the fold of the other. The right angled tip is then tucked between them and possibly even secured by a single stitch where all of the tips overlap.'

c, 'Another method is to have the letter wrapped around a round piece of leather. It is closed. The way it is closed is not to clear. However, Pacioli, stresses that there are special tongues with rounded tips to crease the letter shut. Upon opening the crease marks will be obvious making it a hard task to restore the letter to shut state.'

It seems to me that the third method is a good description of the Chickenwire Letterfold.



Two examples of letters folded using the basic rectangular letterfold method can be seen in an engraving of Erasmus of Rotterdam by Albrecht Durer dated 1526.



In or around 1607 Sir Robert Cecil, Secretary of State for King James I/VI wrote a letter to his teenage son William which includes the following passage:

'I haue also sent yow a peece of paper fowlded as gentlemen vse to write theire letters, where yours are lyke those that come out of a grammer schoole.'

This is clearly not very complementary to young William's folding skills. Unfortunately, while the letter has survived the exemplar has not.

Source: https://blogs.helsinki.fi/kaislani/2016/03/11/letterlocking/



'Magiae Naturalis' by Giambattista della Porta (1535-1615) was first published in Latin in Naples in 1558. The first edition contained only four books but this had gradually expanded to twenty books by 1584. An English translation of the twenty book version, under the title 'Natural Magick' and giving the author's name as John Baptista Porta, was published in London in 1658. Book 16 - 'Of Invisible Writing' of the English translation describes how to defeat a letterlock.



The paragraph mentioning 'folded and perfumed' love-billets below appeared in a story called 'The Maid's Stratagem' in The Lady's book (aka Godey's Lady's Book) of March 1833.



There is a reference to 'three-cornered notes and billet-doux' in the September 1861 issue of Godey's Lady's Book in a brief article describing how good submissions to the magazine are to be made.



The Cahier de Adele Tissot, which can be dated to 1876, contains a folded example of what appears to be a Basic Rectangular Letterfold, except that it is called 'Le Sachet' and thius appears to be intended to function as a container of some kind, perhaps?



A method of folding a love letter appears in 'Winter Nights Entertainments' by R M Abraham, which was first published by Constable and Constable in London in 1932.



A way of folding a letter into a 'Lettre Sans Enveloppe' appears in 'Au Pays des Mains Agiles', which was published by Editions Fleurus in Paris in 1949.



The extended version of 'El Mundo de Papel' by Dr Nemesio Montero, which was published by G Miranda in Edicions Infancia in Valladolid in 1951, contains a design for a letterfold derived from The House titled 'Papel y Sobre' (Paper and Envelope)