The Secret Revealed

Printing with movable type was both inspiration and perspiration, an idea and an invention.

The birth of the idea sounds as if it ought to have been a sudden revelation, a Eureka! moment like the one that inspired Archimedes to leap from his bath with his famous yell. But ideas seldom jump into the mind from nowhere. If they do, like Leonardo da Vinci’s sketch for a helicopter, they remain science fictions until technological advance makes them seem prescient. Ideas are seeded in frameworks of previous growths and need those same frameworks – in this case, punch-making, casting, metallurgical skills, wine- and oil-pressing, papermaking – to flourish.

The growth of the idea seems to have been a slow process. First, perhaps, came a generalised notion, an ‘if only’, the sort of thing that one might discuss over a few beakers of Mosel with an old friend. If only there was some way of getting away from scribes and woodcuts to make texts available fast, everywhere, all at once – well, just think what it would do for the status and wealth of the man who could come up with that. There’s no knowing how it all began; but let’s perform a thought experiment playing with the stages through which Gutenberg must have worked to turn ‘if only’ into an idea, and an idea into reality.

Compared with an inventor in any preceding culture, Gutenberg had the terrific advantage of working with a few dozen symbols, as opposed to several thousand, and with the tools in traditional use for imprinting metal. In a sense, the start of a solution had been right in front of his face from childhood. Individual letters existed on the end of the punches used to imprint book-covers and dies for coins. I can imagine Gutenberg staring at a handful of punches and realising that it would be possible to cut off the top centimetre or so of his punches, bind a few together to create a word, a line, a whole page of metal letters, ink them, press them on to paper, and lo: printing with movable type.

Just examine this, not as a final solution (it isn’t), but as a stage in our thought experiment. A collection of punches could, in theory, be an advance on a wood-block, in that metal lasts longer than wood and makes a sharper image, and the letters could be reordered to change the message, but these advantages are nothing against the major disadvantage: any one page would demand a huge number of punches. Imagine trying to make up dozens of pages like this, with every letter made by a punch-maker. You would have punch-makers working round the clock. And each punch would be unique, with the near certainty that some versions of a t, for instance, would look different from every other one. It takes a good punch-maker a complete day to make a punch. You would need 3,000 just for a single page like the one you are reading now. Ten punch-maker years per page! A complete nightmare, economically a non-starter, totally impractical, ten times worse than working with Chinese.

The problem redefines itself. What is needed, we now see, is a system that reproduces copies of punches. In modern terminology, what Gutenberg was after was something that would multiply each single punch, or part of it – each shank and letter – cheaply, as many times as necessary, leaving the original, as it were the brain of the operation, intact. In brief, what is needed is a new stage – a bridge – in the transfer of images from steel-engraved letters on a punch to printed letters. In modern terminology, the information has to be cloned – a perfect copy of an enduring original. It is the copy that will then produce the new medium itself, the printed page.

So the question now becomes: how do you make a cheap copy of a punch? Obviously, it has to be done mechanically, because re-engraving is out. Now a punch with a letter is a simple thing, but it consists of two elements: the letter on the end (the information), and the shaft from which it has been carved (the support for the information). The letters are all individual, of course, but the shafts must also vary in width because wider letters (like m and w) take up more space than narrow ones (like i and l). Copying a letter was easy – any coin-maker or medal-maker could do it, simply by punching a design on a mould and pouring gold, silver or whatever into the mould. But how do you make copies, in such a way that you can bind those copies together into a form that is both firm enough to print from and flexible enough for reuse?


This question brings us to the key elements in Gutenberg’s work, the bits that actually turn the idea of printing with movable type into reality.

The first element is an image of a letter struck or punched into a little piece of metal. The metal sliver now contains the information you need, the letter-shape imprinted in intaglio. In time, this little item became known as a ‘matrix’, a word taken from the Latin for ‘mother’ – mater – with an ending that made it active. Originally the matrix, the ‘mothering-agent’, was a biological term for the womb or the formative part of a plant. It’s a good image, because this letter, imprinted in metal (copper is best), is the point of origin for the type. (Incidentally, the word ‘matrix’ later suggested to German typefounders, all of them male, a suitably masculine term for the punch: they coined the term ‘patrix’ (Patrize) in the nineteenth century, and the patrix-matrix (Matrize–Patrize) combination became established terminology in Germany; and occasionally the English-speaking world, too.)

The problem now is to transfer the information – the imprinted letter – on to the end of a punch-like little rectangle of metal, producing the same letter in relief and creating a piece of type.

And so to the heart of Gutenberg’s invention, which comes in two parts: an invention and a technique.

The invention is the hand-held mould. This was truly something new under the sun, something so simple to use that it became a standard piece of equipment for typefounders over the next 500 years, until it was replaced by mechanical typecasting in the late nineteenth century.

Simple to use it may be, but the hand mould is fiendishly difficult to understand from a description. To tell you how it works in detail would be as fruitless as using words to teach someone to tie shoelaces or to ride a bicycle. No one bothered for over two hundred years, until Joseph Moxon – London printer, author of technical manuals and maker of globes much admired by Samuel Pepys, among others – wrote a standard textbook, Mechanick Exercises on the Whole Art of Printing, in 1683. He took thirteen pages to deconstruct what any typefounder’s apprentice learned in less time than it takes an eight-year-old to teeter along on two wheels. It’s hard to believe that such a small and practical object would generate such technicalities. In Moxon, you find more than you will ever wish to know of carriage, body, male gauge, mouthpiece, register, female gauge, hag, bottom plate, mouth, throat, pallat, nick, stool and spring, each given its own section and array of subheads. Naturally, Moxon provided a picture to accompany his text, but even then he couldn’t get across what he was talking about. When Moxon was reprinted in 1958, the editors, Herbert Davis and Harry Carter, added a sharp footnote: ‘No one who is unfamiliar with the typefounder’s hand mould should try to understand it by reference to Moxon’s plates.’ Take it from me – the coast of Norway is a doddle compared with Moxon’s description of the hand mould.


Yet the thing is a joy to use, as Rainhard Matseld reveals daily to tourists and schoolchildren by the hundred in Mainz’s Gutenberg Museum. His performance is like a magic show, complete with a puzzling gismo – the hand mould itself – and a retort of molten metal – mostly lead, with additions of tin (to increase the flow and the speed of cooling) and antimony (to harden the metal and thus ensure the sharpness of the letter). He doesn’t let people too near the molten metal, not simply because of the dangers of its 327°C (621°F).

Antimony deserves respect. The silvery ore was much used in antiquity for make-up and as a means of chemical purification. It was said that monks, impressed by its chemical effects, swallowed it to purify their bodies. Unfortunately, antimony is deadly poisonous, so the only things they purified, if anything, were their souls. Almost certainly this is a piece of nonsense based on a false etymology that derives the metal’s name from anti-monos – ‘anti-monk’. In popular parlance it was ‘monks’ bane’. Actually, ‘antimony’ was probably taken from the Arabic ithmid in early medieval times, but the story acts as a reminder that Gutenberg and his successors were engaged in hazardous experiments. Moxon warns typefounders to build their ‘furnances’ near windows ‘as that the Vapours of the Antimony (which are Obnoxious) may the less offend those that officiate at the Making of the Mettal’.

Herr Matseld is about to work his alchemical magic, which should not be spoiled by too close an analysis. All you need to know is that the hand mould has two parts which slide together to grasp the matrix, with the imprinted letter facing upwards. With the matrix held firmly in place by a springy metal loop, the two parts leave a rectangular slot, at the bottom of which is the matrix with its imprinted letter. Herr Matseld takes a ladle, scoops up molten metal, pours an egg cup’s worth of it into the slot, lifts off the spring, slides the mould apart, and out falls a little silver rectangle, just over four centimetres long, already cool enough to hold. This is the product, the offspring of the patrix and matrix, and might have been called the infantrix, if anyone had thought to coin the word. This is a piece of type, or ‘sort’, with its letter standing proud at the top. The whole operation takes less than a minute.


A sixteenth-century typefounder. The artist wisely did not try to include details of the hand-mould.

Herr Matseld’s hand mould, like thousands of others in typefoundries around the world, is the modern counterpart of the invention that lay at the heart of Gutenberg’s work, or so many researchers believe. It could well have been a primitive version of this device that he wished to keep secret, that could have been held together by a couple of screws, that would have fallen apart without them, and which then would have looked like nothing more than a couple of pieces of a three-dimensional jigsaw. Unless you put it together just so – the two bits of the hand mould and the matrix – you wouldn’t have a clue what it was for.

The hand mould provided the essential hardware for the printing process. Here was a device, easily used, which could produce all the amount of type needed for a book from a single set of punches. Later, expert typefounders could make four ‘sorts’ a minute – several hundred (the alleged but unsourced record stands at 3,000) in a day.

The huge advantage of this system was that the type itself was ephemeral. In a large print run of books, it would wear out. But that didn’t matter. You could always make more letters, and if necessary melt down the old ones for reuse. As long as you had the matrices, you could cast more letters; and as long as the punches were intact, you could make more matrices. However primitive Gutenberg’s initial device, the principle was the same: punch (or patrix), matrix, hand mould, type – this was the basis of Gutenberg’s media revolution.

Incidentally, it would in theory be possible to dispense with the punch altogether simply by engraving the matrices direct. Later, printers traded collections of matrices to avoid the expense of punch-cutting. But you have to resort to punches eventually, because it is far easier to cut away dead metal to form raised letters, rather than to incise them. Incising was popular with the Romans, but they dealt in large-format stone letters. Just imagine trying to file smooth the inside edges of intaglio letters the size of the ones you are reading now – it was such a finicky business that punch-cutters commonly used counter-punches to strike un-get-at-able indentations, like the hole in the top half of es and As. The matrix remained dispensable, the punch fundamental.

Now to the second part of Gutenberg’s innovation: the technique of binding the type into a ‘forme’. Not a difficult concept, this gathering of type together into a frame, and fixing the lines to make up a page of metal type. The problems, as Gutenberg would discover, are not conceptual but practical – accuracy of setting, minute gaps to be created, text to be justified so that it looks just right. But this technique Gutenberg seems to have tried in Strasbourg, for the trial transcripts actually mention ‘formes’. Perhaps it was only the ‘formes’ that vanished. But how could there have been pages of type without a means of making the type – the hand mould?

Years of experiment lay ahead to perfect the elements of the hand mould. Every impression punched in the matrices had to be the same depth, to create letters that stood clear by the same amount. Every bit of type had to be exactly the same height as all the others, or some letters would be too heavily impressed and others might not reach the paper at all. Letters fit together in very precise ways, with variable gaps between them that affect their readability. The hand mould had to accommodate microscopic variations to allow broader letters (m, w) to take up more space than narrow ones (l, i); and allow small letters (which typesetters would later call ‘lower case’ because they lay more readily to hand in the lower of two boxes) less space than ‘upper-case’ capitals; with all the variations coming in different sizes of type, now measured in ‘points’; and typefaces; and punctuation marks – all needing their own punch–matrix combinations. Any one typeface needed up to 300 different punches, with each steel-engraved letter and every type cast from it, and every line made up of those letters, made and set to an accuracy measured in hundredths of a millimetre.

Gutenberg also had to refine dozens of other sub-technologies – the business of storing type, composing it, setting it in multiple pages, getting it on to a suitable press, making the right paper, manufacturing the best sort of ink, and then ensuring quality control to make sure the same standards applied right through the publication. As printers soon discovered, they were entering a universe of expertise and had to devise encyclopedias of technical terms.

Take two of these elements, press and ink.

Though the very word ‘press’ became virtually synonymous with printing almost at once, before printing took off it was not self-evident that ‘pressing’ was necessary. It is possible to run off copies by laying paper on a raised, inked pattern simply by hand, or with a cloth. But experiments would have shown that parchment and rag-paper needed to be impressed to make a sharp image. Primitive presses, with great wooden screws that could be turned to force down a plate, were easy to come by. They had been used in paper-making to squeeze sheets dry, and these in their turn derived from pre-Roman presses used for wine- and oil-making. The problem would have been to adapt this technology to printing – to position several pages of type, set into a solid block of metal sometimes weighing as much as a grown man, so that the plate of the press descended fair and square with an equal pressure on every square centimetre, from outer edge to centre.

For making ink, Gutenberg would have known to use linseed oil, soot and amber as basic ingredients, but he would have had to experiment to see what combination worked best. He would have discovered that printers’ ink needs to be a substance of great complexity. The oil for the varnish had to be of just the right consistency, the soot – which was best derived from burned oil and resin – had to be degreased by careful roasting. If he was already considering coloured inks, as he would have to if he wished to rival scribal products, he would have needed to consult artists, and thus learn to use cinnabar – the vermilion crystal once believed to be the blood of dragons – and the rare azure mineral known as lapis lazuli for blue, both of which would need grinding and mixing with varnish in just the right proportions.

Problems must have accumulated with every trial, as type, ink, paper and pressure all interreacted.

For example, how soft or hard should the paper be? A crucial question, the answer to which proved central to the printing operation from then on. Paper designed for quills and scribal inks turned out to be too hard to accept ink on a printing press. It had to be softened slightly by dampening so that the type made a physical indent. Every single sheet of paper had to receive just the right amount of moisture; not too much, or it would dissolve. Trial and error showed that the best way to do this was to dampen alternate sheets, and put them together under pressure for a few hours; long enough for the moisture to permeate, but not too long, or the sheets would start to rot; the whole operation varying in length with the seasons. Then, after printing, every sheet had to be dried; not only the ink, but the paper itself. Forgive the diversion, but as we tap our keyboards and click our print icons, it’s as well to remember the planning, the labour, the care and the time it once took to process words.


A papermaker raises the wet slurry ready for drying.

That was just one unknown among many. How could pressure be applied evenly? How much pressure applied ink best? How soft or hard should the paper be? What happened when different inks reacted with different papers? How to apply the inks so that there was enough to create strong images, without filling up the little holes in letters like es and as? Every element had to be configured afresh, and then reconfigured as it reacted with other elements in a chaos of chemicals, pressures, sequences and timings. No wonder it took years.

And, given the lack of evidence, no wonder that experts argue about what exactly was achieved in Strasbourg. Perhaps tradition offers as good a guide as formal history. Several medieval writers credited Gutenberg with the breakthrough in 1440 – a Florentine named Matteo Palmieri in 1483, a Cologne chronicler in 1499, the German historian Jacob Wimpheling in 1505 (actually, Wimpheling doesn’t name Gutenberg but credits an unnamed citizen of Strasbourg, who carried the idea to Mainz, where it was brought to fruition by Gutenberg). It seems fair to assume that by 1440 or thereabouts Gutenberg was on track to fulfil the contract he had made with his partners, and that this was indeed the ‘adventure and art’ of printing with movable type.

But no one at the time ever said that he got beyond research and development, and actually printed anything. That suggestion, as we will see, emerged only recently.


Gutenberg remained in Strasbourg until 1444. The few surviving documents reveal little about his later life there. He was guarantor for a loan, in circumstances that show he preserved his upper-class status. Whether he actually made mirrors or not is unclear. If so, the operation did not make him rich, for in 1442 he took out a loan himself (eighty dinars, or about sixty-seven gulden). Cash flow, perhaps. But he paid the interest on time for the next thirteen years and stayed in business, presumably pursuing his research and development, having – again presumably – replaced the press lost as part of Andreas Dritzehn’s estate. Indeed, one of his assistants was to open Strasbourg’s first printing works sixteen years later, another hint that his invention had its roots in the city. He remained secure financially, with assets valued at 400 gulden in 1443, enough to sustain him in his long-term aims, even with no breakthrough.

He remained in Strasbourg long enough to see out the term of his five-year contract with his partners. That was hardly a reason to stop work and leave town. There was another, rather more persuasive one: the threat of war. The threat came from a raggle-taggle army of unemployed French mercenaries. They were mainly from Gascony, a traditional source of mercenaries, but were known as Armagnacs because their original leader had been from Armagnac. For thirty years the Armagnacs had supported the French king in his struggles against Burgundy, which was virtually an independent nation in the fifteenth century. In 1435 France and Burgundy joined forces against the English – this was during the last stages of the Hundred Years War. The Armagnacs suddenly found themselves without a role, without jobs, without pay, and 20,000 of them went on the rampage across Europe, a barbarian horde as savage as Visigoths. Frederick III, Sigismund’s successor as German king, thought he could make use of them, and turned them against the Swiss, who were busy fighting for independence. After a fearful battle outside Basel, they burned and pillaged their way north, to Strasbourg.

‘Peace be with you,’ a monk is supposed to have greeted them.

‘Why peace?’ came the rude reply. ‘The war brings me wages and bread. Do you want me to go hungry?’

Strasbourg’s citizens held off these foul creatures, the ‘Armagnaken’, whose name they garbled into ‘Arme Gecken’ (‘poor fools’). Early the following year, 1445, the Armagnacs dispersed back into their homelands, leaving a ravaged countryside and much fury at Frederick for what he had unleashed.

Meanwhile, Gutenberg had left, perhaps unwilling to risk his life for a city of which he never became a citizen, perhaps because war threatened his work, based as it was outside the city walls. Anyway, in 1444 he vanished into limbo for four years, carrying his ambitions and discoveries (though not, I think, any printed books) with him.

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