|Original Title:||Imprimerie en caractères|
|Volume and Page:||Plates vol. 7 (1769)|
|Translator:||IML Donaldson [University of Edinburgh and Royal College of Physicians of Edinburgh, firstname.lastname@example.org]|
|Original Version (ARTFL):||Link|
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. To use this work in a way not covered by the license, please see http://quod.lib.umich.edu/d/did/terms.html .
|Citation (MLA):||"Letterpress printing." The Encyclopedia of Diderot & d'Alembert Collaborative Translation Project. Translated by IML Donaldson. Ann Arbor: Michigan Publishing, University of Michigan Library, 2011. Web. [fill in today's date in the form 18 Apr. 2009 and remove square brackets]. <http://hdl.handle.net/2027/spo.did2222.0001.562>. Trans. of "Imprimerie en caractères," Encyclopédie ou Dictionnaire raisonné des sciences, des arts et des métiers, vol. 7 (plates). Paris, 1769.|
|Citation (Chicago):||"Letterpress printing." The Encyclopedia of Diderot & d'Alembert Collaborative Translation Project. Translated by IML Donaldson. Ann Arbor: Michigan Publishing, University of Michigan Library, 2011. http://hdl.handle.net/2027/spo.did2222.0001.562 (accessed [fill in today's date in the form April 18, 2009 and remove square brackets]). Originally published as "Imprimerie en caractères," Encyclopédie ou Dictionnaire raisonné des sciences, des arts et des métiers, vol. 7 (plates) (Paris, 1769).|
Plate I: Letterpress Printing, The Operation of the Case
The image shows the interior of a room containing the [type] cases and with several compositors setting type. This room communicates with a second room containing the presses which are illustrated in the plates that follow. At the back of the room can be seen the door leading into the press-room; there are a number of shelves on which there are boxes of the various type faces with which a print shop must be provided. Beneath the shelves there are cupboards containing the packets of pieces of type, letters, ornaments and various accessories and tools with which the shop is equipped. Near the ceiling can be seen a number of cords on which the printed sheets are spread out to dry.
Fig. 1 A compositor places in the composing stick held in his left hand a letter which he has picked up in his right hand; he seems to have his gaze fixed on his copy held in the visorium by the clip that surrounds it.
2. Another compositor who is moving a justified line of type from his stick into the galley which is placed over the [compartments holding] the small capitals in the case.
3. Another workman who has imposed two pages in folio format in the chase and is tapping them down with the block held in his left hand so that all the letters are at the same level. He strikes the block, which is a cube of wood, with the end of the handle of the hammer held in his right hand. The imposing stone which is very flat is supported by a sort of table in which here are drawers holding his equipment. Near a corner of this sort of cupboard is seen a folio chase and on the other side a chase without crossbar which is called a Ramette and in which one imposes notices and other work which is not divided into pages.
Lower part of the plate.
4. This contains seven objects:
a a quad used to fill up white space in a line. The type is seen from the nick side and the nick faces downwards as with all the type when it is placed in the stick  its length and thickness are equal so that its base area is perfectly square.
b the letter S of the word Salut that forms part of the third line in the example shown in figure 6 at the bottom of the plate. It can be seen that the letter whose body-height is ten and a half lines is higher by about two and a half lines than the other type round it, the large and small quads and spaces being only about 8 lines high.  The nick which is near the foot of the letter faces downward in the stick as can be seen in the next figure (i.e. Fig 5)
c quads also used to fill the white space but with their width that of their thickness; the nick only extends along half the width of this quad. There are also quads whose width is 3 , 4, 5,& 6 times the thickness of the type body.
d a half-quad whose width is half that of the quad a that is to say equal to half the thickness of the body.
e another quad only half the width of the half-quad.
f a medium space
g a thin space; all these spaces are used to separate words and to justify lines of type. To facilitate justification there are also there are also spaces intermediate in size between those shown, and yet thinner ones, than that shown in g (hair spaces); for each body-size there are five or six sizes of space.
5. Composing stick in which can be seen part of the third line of the type shown in the figure below.
b the letter S beginning the word Salut
e space separating the words Salut and aux which is followed by another space to separate the word ARMES
f the letter A with the nick facing downwards, this letter rests against the space e and is followed by the letters RMES which complete the word ARMES; then follow a full stop and the number of small quads and thin, medium and thick spaces needed to fill the stick completely. The line is the justified as seen in the third line of the next figure (Figure 6).
6. Part of a forme of Gros Canon roman and italic type seen in perspective. The areas of the type face in relief which receive the ink and transfer it to the paper are clearly seen. They are intended for comparison with the proofs of the characters that served as models for this type [i.e. for the punches for the face] and with the printed proof which is on the verso of the last leaf of this explanation so that the reader is able to see the design and the proof at the same time when the book is opened.
Proofs of the type shown at the bottom of the Plate opposite [Plate I] from which it can be seen that it is the parts of the character in relief, shown in white on the plate, and not the concave areas cut out of the type face, that have deposited on the paper the ink that they received from the ink-balls. [i.e. only the areas of the type in relief have printed]
The first line contains the words G loire à DIEU. The G at the beginning of the first word is from one of the sets of capitals intended for posters etc. called petites de fonte ; the following letters are small capitals of the Gros Canon roman face the à is from the lower case roman and is separated from the preceding word by a large and a small space and from the following word DIEU in large capitals by a wide space; a half-quad completes the line and justifies it. Because the body-height of the G is greater than that of the body of the rest of the type used in this example, a line of quads of Saint-augustin body size has been added to make up the height of the letter of the petites de fonte body [i.e. the initial capital G].The second line contains the words Honneur au ROI in italics; the line begins with a quad and a thin space which have been added only to ensure that the G is centred vertically above the H ; the white space attached to the character H would otherwise have made it appear to be pushed into the line. 
The kerned letter H follows the thin space.  By a kerned letter is understood one of which part overlaps the following letter as is the case for the top of the second limb of the H which seems to anticipate the body of the letter o ; this also ensures that the letters come closer together and avoids white space between two letters within a word which would make it appear to be separated it two separate words as in the following example: Honneur, H onneur . In the first case the H is kerned, in the second it is not and one sees in the second case that the letter H is too far from the rest of the word which it begins. Kerned letters are cast in the same mould and with the same matrices as unkerned ones but the register E in fig. 3 of Plate II of type founding is moved aside from the register of the other half of the mould ( fig. 2 of the same plate) so that the blancs C of the mould cover the image on the matrix M by the amount that one wishes the kern of the kerned letter to extend beyond the prism of its body. In this condition the letter cast will be kerned and its imprint on the paper will be closer to that of the letter following than if it had been cast unkerned; the author of the article on Typefounding has omitted to mention this in his account.
The word Honneur is separated from the word au by a thick space as is the latter from the word ROI set in large capitals; the line is justified by a quad; the letter I that finishes the line is also kerned.
The third line contains the words Salut aux armes in a roman face; as in the preceding case the line begins with a quad and a thin space followed by a capital S and the letters alut in lower case roman the a thick space follows before aux . A similar space is followed by the word A rmes of which the first letter is a large capital and the rest are small capitals [small caps]. Finally, after the full stop, the line is justified by two thin spaces and a half-quad. In the figure the height of the characters and the sticks at the bottom of the letters; the nick of all the pieces of type faces towards the line above. 
Plate II: Letterpress Printing, The Case, Continued, Tools and Equipment
Fig. 1 A composing stick dismantled. The surface a b is that against which the foot of the type rests. The surface e d is that against which the nick of the type lies . b c is the closed end of the stick; the lower surface carries various holes into which can be put the screw of the slide to set the line length [the ‘measure’].  The upper slide is f g , the lower slide is h k .
2. The stick with its two slides in place. The measure for the text is c h while h f between the two slides is the measure for additional material (marginal notes). The screw m holds the slides in place. The stick is made of copper or iron.
3. A wooden stick; these come in various sizes. The measure is set in this type of stick by adding quads at the end of the stick opposite to the handle so that the space left within the stick is the required line length. 
4. The nut for the screw holding the slides, in perspective.
5. The screw in perspective.
6. The nut in profile.
7. The screw in profile.
8. Visorum ; the lower spike fits into holes bored in the separators of the case as seen in fig. 1 of the preceding Plate (Plate I).
9. The visorum or copy-holder on which the copy or manuscript is held by two clips.
10. The clip of the visorum; it is wrapped with paper to prevent the back of the jaw from slipping and to adjust it to the thickness required
11. The clip in perspective.
12. Geometric view of the clip.
13. A galley for folio format. A is the slide which is partly withdrawn from the galley.
14. A quarto galley placed obliquely in the way that it is put over the [compartments holding the] small capitals of the roman case; it holds three lines of set type
15. A galley for duodecimo format (12 o ). This galley has no slide; it serves also for octavo 8 o and smaller formats. The galleys are held on the sloping surface of the case by tabs behind the corners a & b [on Fig 1 of the next plate, III]. These tabs fit into the pigeonholes of the case and rest against the dividers that form them in such a way that the galley cannot slide down across the case.
Plate III: Letterpress Printing, Case
Fig. 1. A case of roman type laid out  in the way used in Paris. The upper part AB b a is called the upper case and holds the large and small capitals and least frequently used other characters. The lower part is the lower case and holds the small letters which are used most frequently in setting type for books. The italic case is laid out in the same way as the roman.
2. The roman and italic cases mounted on their stand in the form of a lectern. A B E D the two roman cases. B C F E the two italic cases. The two shelves G H, g g h h underneath the cases hold the pages as they are composed. For how to read them see the article Printing.
Plate IV: Letterpress Printing, Greek Case and Upper Case of the Second Part
The large greek case made up of six sections arranged in two parts, one of two and the other of two rows of two sections in the same way as the four sections of Figure III comprise the roman and italic cases.
Fig. 1. Plate IV. The first part of the greek case made up of two sections. The upper section contains the capitals and the ligatures of the letters mu kappa and theta (μ κ θ). The lower part holds ligatures of the letters epsilon, delta, gamma and alpha (ε δ γ α).
2. Upper section of the second part. This case holds individual letters and some abbreviations, spaces, accents and other diacritical marks etc. found in Greek books. This section is really the lower case in front of which the compositor usually stands.
Plate V: Letterpress Printing, Greek Case, Lower Case of the Second Part and Third Part
3. Plate V. Third part of the greek case placed alongside the two previous parts. It holds the ligatures of chi-theta, sigma-chi, of psi and of chi. The lower case holds those of tau, sigma-tau, sigma-pi and some others as well as quads and other sorts needed for justification. Almost all the letters of the greek case occupy two pigeonholes each, an upper and a lower, which, in the figure are separated only by a dotted line across the upper compartment which is for kerned letters (we have explained the meaning of this term earlier). We have had the shape of the letters and ligatures engraved after those of Robert Estienne and, on the lower compartment that holds the unkerned versions, their transliteration in ordinary characters. Those of the kerned letters that are not placed above the unkerned letter of the same name are placed horizontally beside it and the greek character always precedes the pigeonhole in which the transliteration is written. There is only one in the lower section of the second part, in which we have been unable to show its transcription, this pigeonhole being filled with the two ligatures ouka and ouk; it is above einai in the fourteenth pigeonhole of the second row.
Examples of kerned and unkerned greek letters
This inscription which was on the door of the Academy in Athens where Plato taught means: No one is admitted here who is not a Geometer .
In the first example the letters of each word are spaced correctly whereas in the second the words appear to be cut into pieces.
Plate VI: Letterpress Printing, Impositions
Fig. 1. Chase for folio format. a b c d the chase. f e g the cross  with its two recesses designed to receive the points of the tympan of the press, as will be explained later; the rectangle surrounding the chase represents the imposing stone, it is shown in the same way in all the following figures.
2. Chase for duodecimal (12 mo ) imposition. It differs from the folio chase in having the cross e e running horizontally with no recesses; the points of the tympan must never touch it. There are two different ways of turning the paper to print the reiteration.  The first involves turning the paper vertically about the line f e g of figure 1 so that the edge of the paper which was along b d of the first forme is now along the side a c of the second forme.
The second method involves turning the paper horizontally along the line of e e in figure 2 so that the edge that was along c d of the chase is now along the side a b of the forme for the reiteration.
3. & 4. Imposition of a sheet in folio; these two figures linked by a brace represent: in the first the imposition of the first forme in folio format which contains pages 1 and 4; in the second figure is the second forme or reiteration containing pages 2 and 3. If one imagines that the impression is made vertically in the middle of the white space separating the two formes in figs. 3 and 4 the locations a b c d of the second forme will fall in the same place as the locations a b c d of the first forme, the number 2 of the second page will fall over the number 1 of the first forme and the number 3 of the reiteration will fall over the number 4 of the first forme. If one then imagines a sheet of paper placed between the two formes and printed from them, one would have a sheet printed on both sides at the same time; however, in reality, the two sides are printed one after the other.
In all the succeeding figures care has been take to mark the four corners a b c d of the chases of the first and second formes in such a way as to show how the second forme must be rotated - or, rather, how the sheet printed from it must be turned – so that the correct pages are printed on the second side [verso] of those that must precede them as their rectos. 
The furniture of each of the formes for folio format consists of several pieces of wood whose thickness stands about two and a half lines less above the surface of the imposing stone than the face of the type,  h h are the head-sticks so called because they are at the head of the page ; the pieces l l  together with the metal bar c d are at the foot of the quire  and so are called foot sticks, the corresponding part of the sheet is, in effect, the bottom of the book pages when they are bound or stitched. k k are the side sticks at the external margins of the page and i i are the gutter sticks that form the (inner) margins at the fold of the sheet. Each of the large sticks is held in place by three quoins [wedges] m m m and the smaller ones by two quoins m m . 
To fold a sheet from this imposition it must be held so that the signature A or B (or whatever letter) ( fig. 3) is face-down against the table and on the left with the bottom of the page towards the operator then the right edge of the paper is taken and folded along the middle so that page 3 meets page 2 running the flat of a paper-knife along the fold.
A folio with two sheets per quire [gathered in twos] is impose as follows. The first forme of the first sheet has the signature A on page 1 and contains pages 1 and 8 instead of the 1 and 4 shown in fig. 3. The second side (reiteration) contains page 7 in place of page 3; page 2 is in the same place as shown in fig. 4.
The second sheet contains pages 3 and 6 in its first forme, fig. 3 and has the signature A2 on page 3 which corresponds to page 1 in the figure. The second forme has pages 5 and 4 in place of 3 and 2 in the figure as is set out in the following table. 
Figures 5 and 6. Imposition of a quarto with one sheet per quire (gathering). The letters a b c d at the corners show how the paper must be turned before the second side is printed. The first forme, fig. 5, contains pages 1, 4, 5, 8 and has the signature A on page 1. The second forme or reiteration contains the other four pages, 2, 3, 6, 7. The furniture of each of these formes consists of the gutter sticks k k alongside the cross whose slots receive the points, sticks i i separating the upper from the lower pages , the side sticks l l held by three quoins n n n, and finally the foot sticks m m each with two quoins n n .
A quarto gathered in twos (two sheets per quire) is imposed as follows. First sheet first forme 1, 4, 13, 16, first sheet second forme 2, 3, 14, 15; second sheet first forme
5, 8, 6, 12; second sheet second forme 6, 17, 11, 10. The signature A is on the first page, the signature A2 is on page 3  A3 is on page 5 and A4 on page 7.
These impositions are folded along the middle, corresponding to the cross f g and the holes made by the points the second fold is such that the signature A is outermost; this order is followed in all the other impositions.
7. Imposition of a quarto by half-sheets. All impositions by have sheets have the property that the first pull and the reiteration are made from a single forme.  The sheet is then cut along the holes made by the points then each half-sheet is folded as though it were a folio. The furniture of the chase is the same as for the two previous impositions.
8. Imposition in octavo by half-sheets. In this imposition the paper is turned in the same way as for a folio or quarto so that the edge that was along the side b d of the chase in the first printing is along a c in the second, and the sheet contains two copies of the pages. To fold this imposition the sheet is cut along the row of holes from the points corresponding to the cross f g of the chase and then folds each half-sheet in the same way as a quarto. The furniture for this forme is the same and with the same names as in the previous impositions.
Plate VII: Letterpress Printing, Impositions
9. & 10. Imposition of octavo by whole sheets. Fig. 9 shows the first forme, Fig. 10 the reiteration. The corner letters a b c d on the chase show how the paper must be turned before the reiteration is printed so that the correct pages are on the recto and verso of each leaf. The cross f e g with the gutter sticks l l form the margins, the head-sticks are h h , the side sticks m m and the foot sticks n n ; these are all held in place by the quoins o o o o o o o o o o three for each of the long sticks and two each for the others. The other sticks k k k k and i i i i separate the sets of four pages.
To fold this imposition the sheet is placed so that the long sides pages are facing the operator with the single signature at the left side; the sheet is folded along the holes from the points as for a folio then the end of the sheet with the holes is folded so that the bottoms of pages 12 and 13 face each other, then the fold is creased with the paper-knife. The sheet has now been folded in four; this done, the end of the folded sheet at with the page numbers is folded so that page 8 is opposite page 9, the while sliding the quire towards one to make the folding easier, being sure to keep the signature on the outside.
11. & 12. Imposition of duodecimo (12 mo ) by whole sheets with the offcut inside  and its reiteration using the French style of chase. The four letters a b c d at the corners show that, for this imposition the paper must be turned along the horizontal line of the cross in the centre of the chasse so that the edge of the paper which was along c d of the chase in fig. 11 falls along c d of fig. 12 in the reiteration. The furniture for this imposition are two reglets along the cross of the chase, the head-sticks f f the side sticks m m and the small sticks l l which also hold the sticks along the external margin, as well as the cross with its reglets, the sticks of the offcut ( carton ) g g g g, the sticks h h h and finally the sticks ‘de fond’ i i i , i i i which form the internal margins. The side sticks m m are each held by three quoins n n n , the small sticks have only two each o o .
To fold this imposition the sheet is placed with the long sides of the pages towards one, the first page at the left, then the carton (offcut) is cut off along the row of holes made by the points g g g g in both figures; the carton contains pages 9 to 16 and it is folded once across the centre of its length, then in two making sure that the page numbers fall correctly and leaving the leaf with the signature A5 on the outside. Then the main part of the sheet is folded like an octavo to produce a quire called the grand carton in the centre of which is placed the quire formed by the folded offcut that begins with the signature A5 which is called the petit carton .
13. & 14. Imposition of duodecimo (12 mo ) by whole sheets with the offcut outside using the Dutch chase. This chase differs from those described previously in not having the cross in the middle, instead, with the sticks g g it separates the offcut (carton) from the rest of the sheet. The sheet is rotated horizontally for the reiteration as shown by the corner letters a b c d of the chase as do the letters r and s which are at the ends of the cross whose slots receive the points of the tympan. s s are the sticks for the outside margins; m m the side sticks held each by three quoins n n n, n n n ; l l are the small sticks held by the quoins o o o, o o , which also set the external margins. There are also sticks e e . i i i, i i which set the internal margins. f and f are the head-sticks. This imposition is cut up and folded in the same way as the preceding one except that the carton (offcut) is not put inside the quire from the main sheet. This imposition forms two separate quires with different signatures. That of eight leaves from the main part of the sheet has the signature A and that from the carton of only four leaves has the signature B; thus a book imposed in this way has alternate gatherings (quires) of eight and of four leaves.
15. Imposition of duodecimo (12 mo ) by half-sheets with the carton outside. In this and the subsequent figures the furniture is not shown, it is similar to that of the preceding figures. In this single forme the paper is turned horizontally for the reiteration so that the side of the first pull that was along c d of the chase is along a b in the reiteration . To fold this imposition the sheet is first cut along the horizontal line separating the sheet into equal parts and the two cartons separated from the rest of the sheet by the cross of the chase are cut off and folded. The two large parts of the sheet are then folded as two quartos, each forming a quire of two folded leaves with the signature A. The carton which is signed B forms second quires each of a single folded piece.
16. Imposition of duodecimo (12 mo ) by half-sheets with the carton inside. The paper is turned as for the preceding imposition, that is to say, horizontally and as before there are two copies of the printed sheet. To fold, the sheet is first cut along the line separating the sheet into two equal pieces; then the cartons containing the signature A3 are cut off and folded as folios. The two large pieces are folded as quartos each forming a quire of two folded pieces. The quires from the cartons are then inserted in the middle. 
Plate VIII: Letterpress Printing, Impositions
17. & 18. Imposition of 16 mo (sixteens) by full sheet and its reiteration. For the reiteration the paper is turned horizontally as for a duodecimo as is shown by the corner letters a b c d on the chases. To fold this imposition one begins by folding the sheet along the line of the points without cutting it. Then the doubled sheet is folded like an octavo taking care that the page numbers fall over each other and keeping the signature on the outside. All the furniture of the formes is named the same as for the preceding impositions so the identifying letters are omitted here and in the subsequent diagrams.
19. Imposition of 16 mo (sixteens) by half-sheet in a single quire, producing two copies on the same sheet. The paper is turned as for a folio so that the edge of the paper along b d of the chase is along a c in the reiteration. To fold a 16 mo half-sheet it is cut through the middle along the holes from the points then the two pieces are folded like two octavo quires. The furniture is the same as before.
20. Imposition of 18 mo (eighteens) by half-sheet. This imposition is sometimes needed for example when a work ends with the number of pages it produces. It must be remembered that, at the reiteration when the paper is turned as for a folio, there are four pages to be transposed; these are the four pages at the bottom against the cross of the chase. To make this clearer the letter R has been put at the bottom of each page with the number of the page with which it is exchange places. Thus 7 and 11, and 8 and 12 exchange places. To fold this imposition the top row is cut along the line of the head-sticks as is shown in the figure by a horizontal line then separated into four parts the two ends 5 , 14 and 6, 13 each of two leaves as shown by the vertical lines; the parts are folded as folios; the two leaves 9 and 10 in the middle are divided into two this makes two flying quires that are put in the centre of each of the two quires of which the sheet is made up. Then the remainder of the sheet is cut into three pieces as shown in the figure with the two outer pieces producing two quarto quires. The four pages 7, 8, 11, 12 remaining in the middle are separated in two along the head-sticks and form two folio quires. The quires are then assembled and arranged inside each other in the order of the signatures A, A2, A3, A4, A5 to make two quires each of nine leaves or eighteen pages.
21 & 22. Imposition of 18 mo (eighteens) by whole sheet in two quires; this is the commonest imposition [for eighteens]. Fig. 21 is the first [outer] forme and fig. 22 the second [inner] forme or reiteration. The paper is turned for the reiteration as for a folio as the four corner letters a b c d show. To fold this eighteen, the strip on the right in fig. 21 and the left in fig. 22 then the two leaves 8, 10, 11, 12 are cut from the top of the strip and folded as a folio quire with the signature A5 outside. The lower part of the strip is folded as a quarto with the signature B of Fig. 22 outside. The rest of the sheet is folded as a duodecimo full-sheet; the four top pages with the signature B form a quire and the eight lower pages with the signature A form another into which are placed the cartons with the same signature derived from the strip cut off earlier.
23. & 24. Imposition of 24 mo (twenty-fours) by full sheet with two separate quires. The paper is turned for the reiteration ( fig. 24) as for a folio as is shown by the corner letters a b c d on the chase. To fold the imposition one cuts the sheet through the middle along the holes from the points that correspond to the slots in the cross and then folds each half in the same way as a duodecimal imposed by full sheet.
Plate IX: Letterpress Printing, Impositions
25. Imposition of 24 mo (twenty-fours) by half-sheet with a single quire; the reiteration is printed from the same forme thus producing two copies of the sheet. The paper is turned for the reiteration as for a folio so that the edge of the paper that was along b d of the chase is now along a c. To fold this imposition the sheet is cut along the holes from the points then the two half-sheets are turned so that the signatures A are at the left then the cartons of four pages on the right are cut off and folded as two quartos to be inserted in the middle of the other quires produced by the rest of the sheets which are folded as octavos; then, to each of these is added the quire with the signature B of which there are also two copies.
26. Imposition of 36 mo (thirty-sixes) by half-sheet of one quire. The same forme is used for the reiteration, and again two copies are produced from the one sheet. The paper is turned as for a folio, the edge b d coming to lie along a c and one has two copies each of two quires. To fold this imposition the sheet is first cut in half along the line of the points, then the uppermost row is cut off, cutting both half-sheets at the same time to make two quires of the signatures B, the two remaining parts containing the signatures A are folded as two octavo quires into each of which is inserted one of the quires of signature B of which two copies were produced.
27. & 28. Imposition of 36 mo (thirty-sixes) by whole sheet of four separate quires. The paper is turned as a folio for the reiteration ( fig. 28) as the letters a b c d show. To fold the imposition one begins by cutting the sheet along the holes from the points then separating each half into two equal parts through the middle of the bottom. The four equal pieces are now each folded as an octavo quire keeping the signatures A, B, C, D outside and the quires are assembled in the same order.
29. Imposition of 36 mo (thirty-sixes) by half-sheet of two separate quires. The reiteration is printed from the same forme turning the paper as for the preceding imposition. The sheet is also folded and cut in the same way but to form two copies each of two octavo quires, one signed A the other B; the lines on the figure show where the cuts must be made.
30. Imposition of 36 mo (thirty-sixes) by half-sheet of two separate quires. The reiteration is from the same forme and the paper is turned as for a folio and the paper is cut along the line of the points. The signature A is put on the left and the six pages are cut off from the right and folded as a duodecimo by half-sheet. Then the strip along the head-sticks is cut from the other piece and folded as a carton in duodecimo and the rest of the sheet is folded into two octavo quires. Then the cartons are placed in the centre of the quires of A and B which are then put one after the other to make one copy; the sheet provides two copies and the lines on the figure show where the cuts must be made.
31. & 32. Imposition of 36 mo (thirty-sixes) [by whole sheet] in three separate quires. Fig. 31 shows the first and fig. 32 the second forme. The paper is turned horizontally for the reiteration as shown by the corner letters a b c d . To fold, the sheet is placed so that signature A of fig. 31 is on the left then the strip on the right is cut off; the latter contains three cartons of quarto for the signatures A6, B5, C5 which are then separated from each other and folded as quartos. Next, the rest of the sheet is cut into three parts with the signatures A3, B2, C2 which are folded like three octavos always keeping the simple signatures A, B, C on the outside; then the three small cartons are put in the middle of the three octavo quires keeping the correct signatures together in their alphabetic order. One copy is then complete.
Plate X: Letterpress Printing, Impositions
33. & 34. Imposition of 48 mo (forty-eights) by whole sheet in six separate quires. For the reiteration, Fig. 34 the paper is turned as for a duodecimo, that is, the edge of the paper that was at the bottom of the first forme c d in Fig. 33 is at the top of the second forme Fig. 34, c d . To fold the imposition the sheet is turned so that the signature A is at the left then the sheet is cut across the middle of its width and each half sheet is cut into three equal parts as shown by the lines between the pages; each of these pieces forms an octavo quire and these are arranged one after the other in the order of their signatures A B C D E F.
35. Imposition of 48 mo (forty-eights) by half-sheet. The same forme is used for the reiteration as is also the case for all the succeeding figures. The paper is turned as for the previous imposition and the sheet is cut and folded in the same way. There are two copies form each sheet each consisting of three quires signed A B C.
36. Imposition of 64 mo (sixty-fours) by half-sheet of four separate quires. For the reiteration the paper is turned as for a folio so that the side that was on the right is now on the left. To fold, one first cuts the sheet through the middle along the points then each half-sheet is cut in two then all four parts are turned so that the signature A is on the left and cut together through the middle as shown by the lines on the figure. Thus one has eight pieces each of which is folded as an octavo; then the quires are arranged in the order of the signatures A B C D to produce two copies.
37. Imposition of 72 mo (seventy-twos) by half-sheet of three separate quires. For the reiteration, from the same forme, the paper is turned as for a folio. To fold, the sheet is cut along the line of the points then a strip is cut off from the right along the length of the half-sheet. This strip contains three cartons in quarto which are separated and folded starting with the signature C5. Then the rest of the sheet is cut into three parts and folded, beginning with the top at the signature C, as three octavos. The three quires A B C being folded thus the three cartons A5, B5, C5 are placed in their centres. The same operations on the other half-sheet produce the second copy. The lines on the figure show where the cuts are to be made.
38. Imposition of 96 mo (ninety-sixes) by half-sheet of six separate quires. The paper is turned as for a folio. To fold, the sheet is cut in two along the line of the points then each half-sheet (which produces one copy) into two equal parts along its length following he lines on the figure to give two strips each of three parts which are then separated and folded as octavos. The six quires are arranged in order of their signatures A B C D E F and the whole operation is repeated with the second half-sheet.
39. Imposition of 128 mo (one hundred and twenty-eights) by half-sheet of eight separate quires. For the reiteration the paper is turned as for a folio. To fold, after cutting the sheet in two along the line of the points each half-sheet is cut along the middle of its length and each of the resulting strips is separated into four equal parts which form eight quires to be folded as octavos and the arranged in order of their signatures A B C D E F G H. The lines on the figure show where the cuts are to be made and these lines are printed on the sheet by rules placed in the furniture.
Plate XI: Letterpress Printing, Twenty-Four Page Imposition, First and Second Forms
Imposition of 24 mo (twenty-fours) in four half-sheets in a single quire. This imposition is unusual in that the foot sticks or quads used in their place are of unequal sizes to compensate for the thickness of the paper. 
Fig. 1 First forme of the 24 mo imposition. A B C D the chase. F G slots in the cross, H, H H the head-sticks, K K the side sticks which are held by three quoins M M M. L L small sticks each held by two quoins N N. The twenty-four pages that make up the forme are divided into six groups each of four pages, by the margin sticks. Instead of head-sticks the pages are separated by quads. Also, in place of the foot sticks a a, b b, c c quads have been used. The base a a has two lines of gros romain [quads]; b b are one gros romain and a saint augustin and a feuillet (a feuillet is a wooden reglet of about a quarter-line in thickness). The base c c is made up of a gros romain and a saint augustin. This forme contains three quires of the signatures A B C. 
2. Second forme of the 24 mo imposition with the same furniture as the preceding figure. A B C D the chase. The twenty-four pages make three quires with the signatures D E F. The bottom d d is made up of two saint augustins and a feuillet . e e consists of two saint augustins and ff of a sint augustin a cicéro and a feuillet .
Plate XII: Letterpress Printing, Twenty-Four Page Imposition, Third and Fourth Forms
3. Third forme of the 24 mo imposition containing three quires with signatures G H I. The base g g is made up a saint augustin and a cicéro. h h has two cicéros and a feuillet and i i two cicéros.
4. Fourth forme of the 24 mo imposition containing four quires with signatures K L M.
The four sheets, each with the reiteration printed from the same forme, provide two copies. To fold the imposition, each sheet is cut in two along the holes of the points then each half-sheet is cut into three cartons through the centres of the margin sticks where the rules are placed. The imprint of these rules shows the binder where he must cut the half-sheet. Each carton contains eight pages which are folded like quartos. The quires are placed inside each other in the order of their signatures A B C D E F G H I K L M. 
Plate XIII: Letterpress Printing, Paper Dampening and Form Washing
Showing the tremperie or soaking room where the paper is soaked and the formes are washed.
The picture shows the interior of the soaking room which is roofed and is paved in such a way as to provide drainage for water coming from the soaked paper and from washing the formes.
Fig. 1 Workman washing a forme in the stone tub;  the outlet of the tub communicates via a pipe with a copper cauldron containing the washing solution  which contains potash which the printer call drogue . The apparatus is shown in more detail in the lower part of the Plate. Near the workman can be seen two formes propped against the wall to drain, after which they are rinsed.
2. Workman or printer’s mate  who soaks the paper to prepare it for printing.
- A Reams of paper on a table separated into mains  of ten sheets.
- B Copper basin holding clean water in which to soak the paper; it is supported by a table of suitable size and has a tap at the bottom to empty the water from the basin when it is refilled.
- C Separate table to receive the soaked paper which is spread out on a waste sheet.
Lower part of the plate
Fig.1. Board on which to unlock formes in folio, quarto or octavo, whose type is to be distributed.  This board has two wooden bars under it about two lines thicker than the height of the type so that the type face is not damaged when several boards carrying pages to be distributed are stacked on top of one another. The board is two feet long by eighteen inches across.
2. Board for distributing duodecimo set by half-sheets; it is ten inches wide and it is two feet long the same as the preceding board.
3. Another board for distribution in of formats set in folio, quarto, octavo etc. by half sheets; it is twenty inches long and twelve inches wide.
4. Details of the apparatus in the top picture.
A B the tank or cauldron containing the lye.
C Cylinder in which a charcoal fire is set top heat the lye used to clean the formes; at the bottom of the cylinder is a grate that holds the charcoal and below it is a trivet that acts as an ashpan.
D Opening lid to allow the lye to be dipped out with the ladle M (shown above the tank) and tipped over the forme in the tub.
E Pipe joining the tub to the tank which is closed at the tub end by a plug to retain the lye covering the forme; the plug is removed to let the lye drain into the tank.
F Spout of the tub G H I K; the latter is supported on two trestles. The edge of the stone tub is bound with iron to protect it from erosion by the chases of the formes which would otherwise soon wear it down without this protection. Lying in the tub can be seen a folio forme and above is the brush L used to clean it.
Plate XIV: Letterpress Printing, Operation of Printing and Printing Press
The picture shows the inside of the press-room. Usually, the press-room is not separate from the composing-room shown in Plate I and in that case the cases [of type] are in the best-lit area of the room and the presses are in the other part. But we have preferred for good reason to show the two rooms separately which could not have been shown on the same drawing without confusion. At the back is seen the door that leads to the composing-room as was explained in the legend to Plate I and there are shelves round the walls holding reams of paper.
Fig. 1 [unnumbered on Plate ] Pressman [first pressman]  who is spreading a sheet of white paper on the tympan of the press taking care to arrange the margin according to the sheet pasted to the tympan; the frisket of the press rests against the wall of the press-room.
2  The second pressman, mate of the first, holding the ink balls one in each hand is inking the printing face of the type. When he has done this he continues to distribute the ink on the balls while the first pressman lowers the frisket over the tympan then lowers the tympan on to the forme; then he takes the bar of the press in his right hand and the handle of the rounce in his left and runs the train of the press in so that the tynpan is under the platen which presses down the tympan and thus the paper on to the forme; then he prints half the forme with the first pull [of the bar] then he releases the bar and continues to turn the rounce until the second half of the forme is under the platen and gives the second pull [on the bar] to finish printing that side of the paper. Then he rolls the train out completely with the rounce, lifts the tympan and the frisket and takes off the printed sheet which he places on his bench beside the heap of unprinted paper as shown in the lower part of the Plate.
As shown in the plate the press is stayed in the vertical position by six braces which push against the roof of the press-room and against the top of the cheeks of the press.
3. Pressman [first pressman of the press on the right] who pulls the bar to print the first pull. He holds the bar of the press with his right hand, with his arm extended and his body leaning back. For greater purchase he extends his right leg forward with the foot resting on the sloping footrest placed near the bottom of the press to give it good support; this sloping rest is called the marchpié. The pressman’s left hand holds the handle of the roller of the rounce which drives the train under or out from the press.
4. Second pressman [of the press on the right in the picture] distributing ink on the ink balls while he examines the sheet that has just been printed to check that the colour [depth] of the impression is the same all over the sheet. He is ready to correct the work if successive pages are of different depths of colour. He must also point out to the first pressman who is working the bar if any faults arise so that they are put right.
Lower part of the plate
Bird’s-eye view of the press of which elevations and perspective views are shown in the two succeeding plates. The train of the press is shown open, the coffin in plan view with the tympan and frisket folded back as required by Fig. 3 of the next plate. 
B C, D, E are the cheeks  of the press which are seven and a half inches wide and three and a half inches thick. a a, b, b are the two round-headed screws on each side which hold the cheeks to the upper cross-piece shown in fig. 4 of Plate XVII. H F M N is the rear train of the press on which the ink-block is fixed. H F FG L is the ink-block. L is the palette with which the ink is scraped up to the corner of the ink-block. G is the brayer,  the second pressman touches one of the ink balls here to take up ink which he then distributes from one ball to the other. O P Q R is the coffin of the press in which is enclosed the stone of the press on which the forme locked up in its chase is placed. The chase is held in place by four wooden blocks placed at the corners placed between the corners of the chase and the inner corners of the coffin so that the forme is fixed firmly in place on the stone. Q q , R r are the hinges of the tympan Q R S T which attach the tympan to the end of the coffin; covering the tympan is a sheet which has just been printed from the forme in the coffin as the two sets of figures 1, 4, 5, 8 indicate . S T V X is the frisket. A s , T t are the hinges that attach the frisket to the tympan. Because of the perspective the pages on the frisket and the openings in the frisket seem shorter than the pages [of type] in the forme; in fact they are exactly the same size  - see fig. 3 of the next plate which is lettered to correspond to this figure.
The printer’s bench - the table to which they give this name – holds the white paper Y and the printed sheets Z is sometimes, in fact, a cupboard as shown in fig. 4 of the picture. Or it may be just a table-top supported by two trestles. In either case it is always placed at the printer’s right with the white paper Y [the ‘heap’] nearer the press almost opposite where the tympan stops when the train of the press is rolled out. This makes it easier for the printer to place the sheets of white paper on the tympan. The pressman takes the sheet by the points a and b with the right hand holding a and the left holding b and carries it spread out on to the tympan Q R S T making sure that the edges line up with those of the sheet pasted to the tympan. This is called setting the margin .
To lift off the printed sheet from the tympan the pressman takes it bay the corners nearest to him c and d and carries it to the pile of printed sheets Z on his bench. Thus all the sheets from the heap Y are moved to Z as they are printed.
Plate XV: Letterpress Printing, Press Seen from the Outer Side
Fig. 1. Rounce  of the train seen in plan. p o the spindle of the rounce; a the handle; c d the cord which is attached to a fixture on the coffin on the handle side; e f the other cord which, having passed under the coffin and its plank is wrapped round the roller and then attached to the support of the tympan. The roller e e has two grooves and three upstanding lips the centre one of which prevents the two cords becoming entangled.
2. The head of the press. X X the head piece seen from in front and above. x x the double tenons which fit into the mortises of the cheeks as seen in fig. 3 which shows the press seen from the side. 2, 4 holes to contain the hooks that suspend the nut of the screw. 6 funnel through which is poured the necessary [lubricating] oil. Below is seen the plan of the head seen from underneath. xx, xx, the double tenons; in the next figure a similar press is shown but with a head with simple tenons since this construction is also used.
3. The press in perspective seen from the side; this figure is the elevation of the same structures seen in plan in the preceding Plate[XIV]. b c, d e the feet of the press which are three and a half inches high by four inches wide. f g one of the cheeks, seven and a half inches wide by three and a half thick. N M the table of the rear train of the press on which is placed the ink-block. G the handles of the brayer. K one of the two supporting pillars of the rear which are three and a half inches square, it is fourteen inches from the cheek; this pillar and its opposite number receive the tenons of the three cross-pieces which are each three and a half inches square. i lower cross-piece; the one above it has its lower face at the level of the top of the lower crossbeam has resting on it one of the ends of the bar of the press. The top cross piece which is not visible in the figure is at the level of the beam h and supports the table H M of the rear train of the press at a height of three feet above the floor.
Between the two cheeks is seen the upper beam x under which the bar appears with its handle marked A; lower down is the plate y and under it the platen z; all these parts are seen more clearly in the elevation in Plate XVII.
O P Q R is the coffin of the press supported by the ribs  r m one of the sides of the ribs which are supported at one end by the cross-piece described above, in the middle by the lower cross-beam and at the other end by the leg n p . o the end of the spindle of the rounce supported by a trunion as is the other end which carries the handle. m footrest on which the pressman rests the foot of his extended right leg while he pulls the bar as can be seen in the picture on the preceding plate. q the end of the table of the coffin which carries the bridge of the tympan. r one pivots of the roller of the rounce round which is wrapped the cord e f in Fig. 2. t the bridge of the tympan. Q R S T the tympan with a sheet of paper spread on it for printing. S T V X the frisket; the arc V u Q shows the arc traced by the frisket when it is folded down on to the tympan and S s P is the path of the tympan as it is folded down on to the forme in quarto format shown on the stone in the coffin of the press O P Q R.
Plate XVI: Letterpress Printing, Press Seen from the Inner Side
This plate shows the plan of the ribs and the elevation of the press seen from the side of the pressman. The following plate contains its elevation and details. As far as possible the same letters have been used for the same parts to facilitate comparison [of the plates].
Fig. 1. Transverse section of the ribs. Q R the sides of the ribs each made of a piece of wood with a groove cut in it. q q r r the four little pieces that support the iron rails 1 2.
2. Plan view of the ribs of the press. F Q, R M the two side-pieces which are attached by two crosspieces Q R, F M which hold the rails passing between the two cheeks D E B C separated by about one foot nine of ten inches which is the width of the ribs.  The ribs rest on the lower cross-beam of the press which can be seen through the three openings between the components of the ribs. d c e f the cord of the rounce. p o the spindle of the rounce. a the handle.
3. Perspective view of the press in elevation seen from the side of the pressman. In this figure can be seen the rear train of the press on which the ink block is placed. b c d e the feet which are three and a half inches high by four wide. B C, D E the top of the cheeks to which are attached the braces that steady the press as seen in the picture on Plate XIV. f g the cheek of the pressman’s side of the press three and a half inches thick by seven and a half inches wide to which is attached the shelf on which the [second] pressman puts his ink balls. k k the two pillars of the rear train of the press which are three and a half inches square; the distance between the pillar and the cheek of the same side is fourteen inches; the height of the table N N H is three feet above the floor. The two pillars are held together at the top and to the cheeks by three crosspieces h h which are grooved into the underside of the table of the ink-block; three more crosspieces i i i strengthen the assembly. The two pillars also carry the cross member 1, 2 on which rests one end of the ribs M R while the other end is carried by the legs n n . P Q is the coffin which holds the forme and the tympan. Near to the point P can be seen the closed end of the gutter  from which the excess water used to moisten the tympan and margin-sheet runs out at the other side of the press; in this same channel which is made of zinc the printer lays his sponge. q t t the bridge of the tympan. r the roller round which the [one end of the] cord of the rounce is wrapped and attached. p the end of the spindle of the rounce. a the handle of the rounce. On the ink-block are the brayer G and the palette L. 
Plate XVII: Letterpress Printing, Development of the Press [Further details of the press shown in the previous plate.]
4. Elevation of the press. b d the feet. g f the cheeks, three and a half inches thick and five and a half feet high including the feet. g g the bottom crosspiece. f f the top crosspiece which holds the cheeks together using four screws with pierced heads ; the screws are embedded in the cheeks which are three or four inches square. x x the head which is six inches thick and the same width as the cheeks; in front are seen the support pillars for the ribs. p p is the plate at the top of the pillars. n p, n p the vertical pillars joined by the piece n n . Q R the two sides of the ribs which serve as guides for the table of the train of the press. The bridge of the tympan and the gutter have been omitted to allow the corner-pieces that hold the coffin together to be seen. z z the wooden upper part of the platen at whose four corners are the fixings to receive the cords  that suspend the platen from the hose.  y y the till  which acts as a guide for the hose. 3 5, the head of the shaft of the screw through which passes the bar 3, 7, 8, A which is retained by a key. 7 the rest for the bar. A the handle of the bar. 2, 3: 4, 5 the nut-bolts that hold the nut in the head. x x the head whose tenons pass through the cheeks; the head is seven inches thick and its width is the same as that of the cheeks.
5. Elevation of the cheek carrying the rest  for the bar seen from inside the press. d the tenon that is mortised into the foot. g g mortise for the bottom cross member. X X, X X the two mortises which receive the double tenons of the winter ; in some presses these mortises pass right through the cheek. y y the till which guides the hose; the till has been cut through the centre of the hole 6 7 through which the hose passes. 5 4 dovetail wedge to fix the till in the clot in the cheek that holds it. 1, 2 the barcatch. x, x x the long mortise that receives the tenon of the head; this mortise passes right through the cheek to better hold the tenon; in some presses this mortise is double as seen in fig. 3 of Plate XV and in this case each end of the head has a double tenon. This mortise is cut longer than the tenon it receives not only to allow the head to be raised or lowered as desired and thus lengthen or shorten the stroke of the bar but also because it is filled with elastic packing such as felt  it makes the stroke of the bar softer. f f the mortise to hold the tenon of the upper crosspiece.
6. The head seen from below. x x its two tenons; 3 5 the nut-bolts that hold the nut in place. Above is seen the upper crosspiece with its tenons ff ff .
7. The winter seen from below with its double tenons X X which fit into the mortises of the cheeks. At the bottom is the lower crosspiece with its tenons gg gg .
8. The two parts of the till which acts as a guide for the hose. y y y y one half of the till with tenons c c which fit into the other half y y that contains mortises into which these tenons fit when the parts are assembled. c d opening for the hose; this opening has a bead round it as have the outer edges of the till as can been seen in the profile view of fig. 5.
9. Perspective view of the platen, its casing, the hose, the screw and the bar. z z z z the casing of the platen; its length z z is sixteen inches and its width z y ten inches and it is two inches thick. This casing is seen separately in fig. 9 number 2, 1, 2, 3, 4 are the four screw-eyes that receive the cords by which the casing is suspended from the four hooks of the hose B C. The figure shows the space into which fits the copper or iron platen; the centre of this platen  is the bearing that receives the shoe or stud  x, fig. 10. l the lower end [toe] of the screw that passes through the hose B C. f g the head of the screw shaft that receives the cranked bar g f h i A. i A the handle of the bar; e e e e the screw with four threads.
Above the screw is shown the nut a c which is brass and has two lugs b & d by which it is held in the head by the hooked bolts 2, 3: 4, 5 fitted with nuts at their upper ends.
10. Details of the screw, the hose, etc. e is the four-threaded screw shown geometrically. f g the head of the screw shaft pierced by two holes at right angles to attach the bar. l ferrule which retains the hose. m double key that goes through the shaft and retains the washer. 1 pivot for the toe of the screw, it is of tempered steel. B B the hose in perspective. n o, n o two of the four hooks by which the platen is suspended; these hooks run in grooves in the front and back faces of the hose and are held in place by two pins as seen in the preceding figure. x the metal box in which is the steel bearing that receives the point of the screw. This metal box fits into the space in the centre of the platen. z y y z brass  plate of the platen the recess and the rings are part of the same casting [as the flat part of the plate].
To make the screw the metal is forged to a suitable size and turned on the lathe so that the part to be threaded is perfectly cylindrical. Then a pattern for the four threads which must be four lines wide and deep is made as follows.
A piece of paper is cut to a width equal to the height of the cylindrical part and length equal to its circumference; these dimensions are found by wrapping the paper round the cylinder. Such a piece is shown in the figure at the bottom of the page. A B and C D are five inches four lines long and the dimension A C and B D is equal to the circumference of the screw. The verticals A B & C D are divided into 16 equal parts B a, a b, b c, v d, d e, e f, f g, g h, h I, I k, k l, l m, m n, n o, o p, p A : D 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16. through the points h and 8 the line h 8 is drawn which divides the parallelogram A B C D into two other parallelograms A h 8 C and h B D 8 then the diagonals h 16 and B 8 are drawn. Then other similar parallel lines are drawn through 9, A; 10, b ; 11, c ; 12, d ; 13, e ; 14, f ; 15, g which divide the parallelogram C h B 8 into eight smaller equal parallelograms. Then the two triangles A h C and B D 8 are divided by lines parallel to the preceding ones which pass for the first triangle through i, k, l, m, n, o, p and for the second through 1, 2, 3, 4, 5, 6, 7. Then to finish the template the space between neighbouring lines is coloured with a brush and that between the next pair is left blank so that one has alternate bands of coulour and of white. Then the back of the template is covered with flour-paste and applied and stuck round the circumference of the cylinder destined to be threaded making the pairs of points D and B and C and A coincide exactly.
When the paper has dried on to the piece of iron the lines of the template are cut into the metal using a chisel struck with a hammer of suitable weight so that the lines penetrate about quarter of a line into the cylinder. Then the parts to be excavated are removed with gravers so that the four concave helices four lines deep are formed. The parts standing proud are the four threads of the screw and the whole is then smoothed and polished with fine files. See also the article Étau  and the Plates referred to there.
Once the screw is finished the nut must be made. It is brass and cast from the screw itself. To do this a pattern of the nut is made in wood and this is put on the screw.  Then a sand mould is made (between two plates) of the nut mounted on the screw; the wooden pattern leaves a space to be filled by the casting metal. The mould is opened and the contents removed then the pattern is removed from the screw and the latter is coated with a thin layer of clay or ochre and heated before replacing the coated screw in the mould and closing it. The molten casting metal is poured in to fill the space left by the pattern and the spaces between the turns of the threads on the screw and thus form the threaded brass nut. The nut must then be removed and adjusted so that there is the necessary play between nut and screw. To facilitate this, the threads of the screw are coated with a little clay or ochre with a brush.
To remove the nut it is hammered on its four faces to spread it a little then put in a square hole in a strong stone block or a strong press [or vise] so that the point of the screw is uppermost, then, with a spanner the square on the screw is turned to the left so that it unscrews from the nut. The screw is cleaned and oiled and screwed in and out of the nut several times to ease it a little. 
Other types of press than that just described can be made in which the screw does not have a hose but instead passes through a two-piece collet which fits round it like a collar. This collar is carried by a brass cross piece with tenons on its ends which fit into grooves cut in the internal faces of the cheeks of the press so that it follows the vertical movement of the screw without turning. The platen of the press is suspended from the arms of the collar either by four or by two vertical rods threaded at their upper ends and [screwed into] the transverse arms of the collar which act to hold them and the keep all the parts parallel to the upper surface of the tympan and the stone on which the forme lies; these rods take the place of the cords z C y C of fig. 9.
Plate XVIII: Letterpress Printing, Development of the Bed of the Press
This plate shows details of the train of the press [the carriage].
Fig. 1. Geometric plan of the coffin and the plank q OP q which forms its base. O P Q R is the coffin formed of four wooden bars two inches square. o O o ; p P p; q Q q, r R r are the four corner pieces of the coffin; t t  the bridge of the tympan.
1. no. 2 Plan of the underneath of the wooden plank. P q q O the plank. P Q R O the sides of the coffin. 1, 2, 3, 4, 5, 6: 1, 2, 3, 4, 5, 6 the twelve pads which slide along the two rails of the ribs ( fig. 2 Plate XVI).
1 no. 3. Profile view of the carriage to show how the cord fixed to one end of the coffin at A passes round the roller [of the rounce] B, passes under the plank and is attached to the roller r on the bridge t of the tympan.
2. The coffin and the plank seen in perspective. t t is the bridge of the tympan; r one of the pulleys which serves to fix the cord of the rounce.
3. The stone of the press . a b c d the four ends of the two cords by which the stone is lowered into the coffin below under which has been spread a bed of chaff to give it a solid seating. The ends of the cords  used to left out the stone lie along the sides of the coffin between the stone and the sides and the space [above them] is filled in with wooden reglets of suitable thickness.
4. The tympan seen from the opposite side to the view in fog. 3 of Plate XV. a, c the wing-nuts of the screws that hold the points. b wing-nut of the screw that fixes the small tympan on to the large one. Q R hinges  of the large tympan which attach it to the coffin. T e S iron bar of the tympan on the side that rests on the platen. d handle of the tympan by which the pressman raises it.
4. no. 2. Plan of the tympan seen from above; the tympan is shown fitted with its skin. a, c holes for the screws of the points. b hole for the screw to retain the piece that fixes the little tympan in the large one. R Q hinges [half-hinges] of the tympan. S T the iron bar.
5. The blankets which are place on the tympan immediately on top of the skin or parchment spread out and pasted on its surface. These are pieces of the woollen cloth known as moelleton  which are cut to the size of the inside of the tympan to make what are called half-blankets twice the size of the tympan which are then folded to form the blanket.
6. The card placed over the blankets in the tympan; this card is made up of several sheets of paper glued together. Underneath it are placed pieces of paper of the same size as, and as many as, there are pages in the forme to be printed; these pieces which must correspond exactly in size to the pages increase the pressure exerted by the platen on the pages. The same method is used to rectify faults in the platen or other parts of the press. 
7. The small tympan fitted with its skin; it is enclosed within the large tympan where it is foxed at one end by three iron lugs riveted through the iron cross bar of the frame, the three other sides which are wooden, or, better iron strips; the three lugs under the iron cross-band of the large tympan, fig. 4. The other end of the frame of the small tympan is held and fixed in the large tympan by a piece held by the screw b in the same figure.
7. no. 2. Plan of the small tympan covered with its skin. In this figure the three lugs 1, 2, 3 are shown which enter under the bar T S of the large tympan. The opposite side b d i s held at the point a by the assembly shown in fig. 10.
8. T S V X the frisket for folio format. T, S the small [half]-hinges by which the frisket is attached to the large tympan (see figs. 4 and 4 no. 2) they mate with the matching [half]-hinges T and S [on the tympan]. a b the openings for the pages. 
8. no. 2. Plan of the frisket seen from the side against the paper to be printed. T S the half-hinges of the frisket; they attach by two pins to those at T and S on the tympan. The frame of the frisket T V X S is made of strips of iron to which the paper is glued; it is then cut out to correspond to the pages on the forme the whole makes up what is correctly called the frisket which masks the paper on the tympan from any ink carried by the furniture of the forme. a and b the openings for the two pages of a folio; 1 the notch to allow the signature of the sheet to print. 
9. Elevation of the bridge of the tympan. q q the plank of the coffin; r r the roller; t t the bridge and its two supports.
10. a one of the points seen in profile with its threaded pin and its nut. b the point in plan; c threaded pin; d nut; e  screw fixing the small tympan in place; f stop for the small tympan; g nut to fix the stop.
Plate XIX: Letterpress Printing, Press, Tools and Utensils
This plate shows various of the printer’s tools and illustrates how the ink-balls are assembled.
Fig. 1. Hammer; about which there is nothing special.
2. Planer (block to tap down the type in the forme). This is made of wood and is struck with the handle of the hammer ensure that no type protrudes above the surface of the type-block in the forme, before the forme is finally locked up. This is why the two tools are shown one above the other.
3. Pair of compasses.
4. Gimlet to make holes in the furniture [of the forme] and to make holes for the points if they foul the furniture.
5. Bodkin for correcting. 
7. Spanner to tighten and loosen the nuts of the points and the screw holding the tympan.
8. Sheeps-foot  used in mounting and demounting the ink-balls; a is a hammer to drive in the nails and b is the sheeps-foot for pulling them out.
9. Scissors for cutting the friskets; there is nothing special about these.
10. Knife for scraping the ball-leathers.
11. Shooting stick for removing the quoins in formes. 
12. Small chisel,  a tool to remove superfluous metal from the body of type so that such burrs are not inked by the balls and so make marks on the paper.
1. The nick on French type was on the side of the body carrying the top of the letter whereas English type had the nick on the opposite side (that of the base of the letter). This must be kept in mind whenever the author refers to the nick. In English typesetting the nick is on the upper surface of the type as it lies in the composing stick where it can be felt by the compositor’s thumb to check that the letter is not inverted.
2. The G is from type of a different, larger, body-size than the rest of the letters though we have not yet been told this!
3. This explanation is confusing. It is the G which would have appeared ‘pushed-in’ with respect to the following line. Had the thin space before the H been omitted, the H would have appeared to the left of the G so the line beginning with H would have been misaligned to the left of the line above it.
4. The kern of the H can be seen overlapping the o in the figure.
5. The sticks that hold the type in the chase are not, in fact, shown in the figure. The nick is not visible since it faces the line above. Note that French type had the nick on the opposite side of the body to English type (see note 1 above).
6. See note 1 above.
7. The text uses the word justification to mean the pre-set length of the line, in English terminology ‘the measure’. The measure was set to the desired line length before composing began by adjusting the slide. The stick illustrated here has two slides one to set the length of the text block and the other for marginal notes as is explained below.
8. This seems a very inconvenient arrangement. I think that fixed sticks were usually made to one particular measure - for example, for a newspaper column - and were used only for setting to this measure.
10. In English this was known as the ‘lay of the case’.
11. barre This is usually called the cross in English printing.
12. La retiration Printing the second side of a sheet usually called in English perfecting but sometimes ‘printing the reiteration’.
13. These rather convoluted explanation simply means so that page 1 will be followed on its verso by page 2 and so on. Achieving this can be quite complicated when many pages are to be printed on a single sheet.
14. So that the furniture is not inked and does not mark the sheet; the mask of the tympan also serves to ensure that ink is not transferred from the furniture to the printed page.
15. les têtieres
16. The identification of the various ‘sticks’ is wrong from here on. I have silently corrected the text so that the letters correspond to the correct furniture in the figure.
17. le cahier That is, at the foot of all the pages printed from the forme.
18. This was the usual arrangement with three quoins along each short (vertical) side of the chase and two on each side of the cross at the bottom.
19. The table is correct but it must be remembered that it shows the formes and not the sheets printed from them. It is easier to think of the printed sheets in which case the numbers on pair must be exchanged left for right. So the first sheet printed from A has page 1 on the right and page 8 on the left; the sheets are picked up and folded so that the fold is on the left. The first sheet has page 1 as the first recto, and when opened along the fold has page 2 on the left (first verso) and page 7 on the right (last recto). As the table shows, how the pages are arranged on the sheets of a quire (also called a gathering) depends on how the book is to be gathered.
20. The table in the original is extremely confusing and is best ignored.
21. This method of working produces two copies of each half sheet since the same type is printed on both sides of the sheet which is turned between printing each half sheet.
22. Duodecimo imposition (12 mo often abbreviated to twelves) was fairly complicated. Before the 19 th century twelves seem to have imposed always using an asymmetric layout in which eight leaves were contained in a large piece of the sheet and the other four in a strip along the side which was cut off before the sheet was folded. This offcut is called the carton in the Encyclopédie. Two general schemes are described here: carton- dedans in which the folded carton (the offcut) was inserted inside the quire from the main part of the sheet and carton-dehors in which it was added outside the quire of the other eight leaves. The layout of the pages on the forme clearly had to be different between these schemes. In addition twelves were sometimes worked by half-sheets, as described in this figure legend.
Duodemino could be laid out without a carton or offcut but Gaskell says this was not practised until the 19 th century. For more details and a concise explanation of imposition of twelves see Gaskell (1974) who provides clear and fairly simple diagrams of impositions in all the common formats. Note particularly that Gaskell’s diagrams show a printed sheet as it would appear on the tympan of the press, whereas the plates of the Encyclopédie show the forme as it appears on the imposing stone. The two sets of diagrams are mirror images.
Gaskell, P. A new introduction to bibliography (second impression with corrections) Oxford, The Clarendon Press, 1974. Figs 54 – 59 and note D pp. 106-107.
23. Both sides are printed from the same forme.
24. The imposition of Fig. 16 corresponds to that of Fig. 59 of Gaskell (1974) which shows the printed sheet. Both this and the preceding imposition produce two copies of 6 leaves or 12 pages.
The ‘whole’ duodecimo format of course contains 12 leaves, that is 24 pages of which these impositions produce the first 12 pages. The second 12 pages are then laid out in the same way on a second half-sheet. In the end the two half-sheets, each printed on both sides, yield two complete copies of a set of pages of the complete format of 24 pages.
25. The legend does not correspond with the figures. I believe the figures illustrate an imposition for 48 mo which, of course, contains 48 leaves and 96 pages. Twenty-fours by half-sheet only require two formes each of 24 pages for the rectos and versos of the 24 leaves.
26. The figures do not correspond to the legend. In the figures ordinary furniture and not quads are used!
27. If this last part of the legend is correct the end result would be 12 signatures each of which contains 8 pages , that is, 96 pages which is the number contained in a 48 mo imposition. Thus the imposition would, indeed, be for 48 mo and not 24 mo . The four formes are each printed twice on the full sheet, giving two copies of the 96 pages.
28. Le baquet We are later told it is made of stone.
29. La lessive This was lye generally made from wood-ash.
30. compagnon Imprimeur
31. See the text of the article for further explanation.
32. For details of distribution of type see the text of the article.
33. The leftmost workman in the picture, putting a sheet on the tympan of the left of the two presses in the picture.
34. The hand-press was worked by a team of two press-men ( compagnons ); see the text of the article for much more detail.
35. The legend treats the workers shown on the plate in a different order to that in which they are labelled on the plate. I have preserved the order in the legend but renumbered the paragraphs to correspond to the Plate.
36. This rather cryptic remark simply means that Fig. 3 of the next plate shows a side view of the train of the press.
37. Les jumelles
38. Le broyon called the brayer by Moxon.
39. These two sets of numbers mark corresponding points on the forme and the printed sheet – those on the printed sheet are not very easily visible.
40. The bird’s-eye view is not of a horizontal tympan and frisket; they are open at an angle as can be seen in Fig. 3 of the next plate.
41. The whole mechanism for rolling the train in and out is called the rounce in English.
42. Le berceau
43. The description is confusing; I have translated it to correspond to what is seen in the figure.
44. Not all these letters and number appear on the figure but the construction is nevertheless clear enough from the illustration.
45. This is probably the structure attaché to the tympan near the letter like an italic q which may be intended to be a p but engraved in error in reverse ?
46. In fact, G seems to be the palette and L the brayer!
47. The screws apparently have a hole through the head through which a tommy-bar could be passed to tighten them.
48. These were often metal hooks or links.
49. Hose: the wooden box through which the screw ran. The hose could not rotate and was driven up and down when the screw was turned carrying the platen with it, The suspension of the platen kept its upper surface in contact with the toe (lower end) of the screw.
50. The hose was prevented from rotating by the square hole of the till through which it passed.
51. The ‘barcatch’.
52. Winter: the English name for the crosspiece supporting the carriage of the press.
53. Matieres élastiques comme de morceaux de chapeaux &c
54. la crapaudine
55. la grenouille
57. Étau A vise. There is an article Etau (no accent) which describes the construction of a vise and uses a similar same method of constructing a template for the screw. Etau The process of turning the shaft and setting out and cutting the thread is illustrated in detail in Toolmaker — Manufacture of Vises, Plates I and II. These refer, however, to cutting a single thread on the blank using a simple screw-cutting lathe and not to a multi-thread screw such as the one described here for the press.
58. The wooden nut blank would simply have to be slid over the screw. As the nut is to be cast on the screw it would not be necessary for a thread to be cut in the wooden pattern, which serves only to define the body of the nut. See later in the description.
59. All this depends on the brass being softer than the steel.
60. Wrongly described as r r in the original legend.
61. Clearly, the cords were used to lower the stone into the coffin then folded along its sides for use when the stone was to be removed.
62. These are really half-hinges that mate with the other halves on the coffin. A pin is then inserted to make the hinge.
63. Moelleton More usually spelled molleton , a soft woollen cloth.
64. The tympan of the hand-press was quite soft and had to be packed up in this way to adjust the pressure over the paper on the type and to correct any unevenness in the impression.
65. The frisket masked the sheet so that only the inked type produced an impression on the paper.
66. The figure 1 is missing from the diagram but the notch is clearly visible in the left opening, a .
67. The screw below f incorrectly labelled c in the diagram,
68. Used to pick out letters from the forme during correcting.
69. Moxon calls the tool the sheeps-foot .
70. This was just a piece of wood used to drive in the quoins and knock them out. English printers called it the shooting stick .