Illustration of Books. Since man first discovered how to convey his thoughts to others by means of writing, he seems to have felt the want of some method of illustration or embellishment. From the Egyptian papyrus down to the invention of printing this was supplied by pictures, coloured or uncoloured, engravings, carvings, &c., executed by hand, and so far as these have any connection with books or writings their history will be found in the article ILLUMINATION OF MANUSCRIPTS. The first printed books were entirely illustrations, both pictures and text being printed from blocks engraved on wood in relief, such as the Biblia Pauperum (q.v.), and many others. The Ars Memorandi (end of 15th century) comprised fifteen New Testament pictures, faced by the same number of text pages, all engraved on wood. The Mazarin Bible (1455), the first book completely printed from movable types, many of the copies of which were beautifully embellished by hand, was sold as a manuscript, till the number of copies aroused suspicion. Many other spurious MSS. were produced in the same way, the larger price obtained for them forming a temptation to those having the secret of printing.
The first edition of the Speculum Humanae Salvationis, said to have been printed by Coster about 1440, is supposed to be the first book in which two different coloured inks were used on the same page; and the ornamental capitals in the Psalter of Fust and Schöffer in 1457 are beautiful specimens of printing in two colours. Probably the first printed book with wood-engraved illustrations used throughout the text was the Fables of Ulrich Bohner, issued by Albert Pfister, printer of Bamberg, in 1461, which had 101 engravings on wood. In Italy the first known example is the Meditationes, published by Ulrich Hahn, a German, in Rome, 1467, of which three copies are still known to exist. The most artistic book of this period was certainly a volume on military art by Valturius, illustrated by eighty-two designs by Matteo Pasti, at Verona, in 1472. The designs are in outline and very cleverly drawn, though poorly engraved.
The invention of the method of printing from engraved (intaglio) plates introduced a new factor into book illustration. Il Monte Santo di Dio (Florence, 1477) was the first book issued with illustrations engraved on metal.
In the beginning of the 16th century many books were beautifully illustrated by pictures in chiaroscuro, produced by three or four blocks, engraved on wood, printing different shades of the same colour, generally ochre, brown, gray, or red, many of the original drawings being by Titian, Raphael, Parmigiano, and other masters. About the middle of the 16th century engraved plates began to be used in conjunction with wood-engravings in the same books; and from this period a struggle for supremacy began between the two arts, which finally resulted in favour of metal at the end of the century. Wood-engraving declined till revived by Bewick, and metal-engraving and etching had the field to themselves. During the 18th century many books were beautifully illustrated by engraved and etched title-pages, vignettes, and tailpieces, the most celebrated artists making designs for the purpose; the type was first printed, leaving spaces on which the plates were afterwards printed. The lead taken by France in the 18th century was closely followed by Germany and England. Coloured illustrations, when not coloured by hand, as they generally were, were printed by means of numerous carefully prepared wood blocks, each printing a different colour. An elaborate account of the method will be found in Savage's work. In short, the history of book illustration reflects more or less faithfully the state of art of the period, and it may be traced in the articles Book, Engraving, Wood-engraving, Bartolozzi, Bewick, Caxton, Dürer, Hogarth, Turner, &c.
The invention of lithography in 1796 introduced a third element, which was immediately taken advantage of. Being much cheaper than steel-engraving, it gradually tended to supersede that process for book purposes, its special adaptability for coloured work giving it great advantages over its rival. In England book illustration may be said to have reached its culminating point as regards engraved and etched plates in the first half of the 19th century, in the series of annuals, keepsakes, and the higher-class books illustrated by such masters as Stothard, Turner, &c. The revival of wood-engraving by Bewick and his pupils gradually led to the restoration of that art as an illustrating medium. In this it was greatly aided by the facility with which wood-engravings can be printed along with the text, together with the advance made in typographic printing. The series of Christmas books illustrated by John (afterwards Sir John) Gilbert and Birket Foster had no small share in that advancement. Among the artists who have helped to raise the art to its present high position may be mentioned Cruikshank, H. K. Browne (Phiz), Doyle, Leech, Tenniel, Millais, F. Walker, W. J. Linton, Herkomer, &c. The development of what has been called the American school of wood-engraving has still further increased the influence of that branch of art for illustrative purposes.
Relief-block Processes for Book Illustration.—
While Photogravure (q.v.) threatens the final extinction of steel-engraving, very many processes have been invented to produce relief blocks with a view to supersede wood-engraving in book illustration. The object aimed at is to reproduce drawings in line or wash, in fac-simile, on a relief block capable of being printed from the surface at the type press. That is, the lines or parts which impress the paper are to be left in relief, while the white parts are cut out so as to leave the paper unprinted.
What are called 'process' relief blocks may be divided into two kinds—those reproduced from black-and-white, or line drawings by pen and ink, and those from half-tone photographs or wash drawings. The former, as being the simpler, we shall describe first.
The simplest form of it is when a drawing is made in transfer ink on lithographic transfer paper (see LITHOGRAPHY), or when a proof of a line drawing on stone or line engraving can be got in transfer ink. This transfer drawing or proof is transferred to the polished surface of a zinc plate in the ordinary lithographic manner. Zinc is generally used, because it is cheap, and is readily soluble in etching acid; but copper is sometimes used for very fine work. After the transfer the plate is wetted, and the lines are inked repeatedly till a thick coating of ink covers the lines of the drawing. Powdered asphalt, or other similar substance, is then dusted over the plate, which is gently heated till the asphalt is incorporated with the ink. The back of the plate and the other parts not requiring to be etched are covered by varnish, and the plate is put into a bath of acid for the uncovered parts to be etched away, leaving the lines in relief. As the etching, if carried on continuously, would undermine the lines and finally eat them off altogether, the plate is removed from the bath after a very slight etching. It is then washed and gently heated, which causes the asphalt and ink to run down the side of the lines already in relief, and protect them from further etching. This is a very delicate part of the process, and great skill is required to let the protecting compound run down enough and no more. The plate is returned to the bath and etched a little more. The washing and heating is repeated, and so the etching and heating goes on gradually till a sufficient depth is obtained for the fine parts. During the etching a rocking motion is given to the bath to make the acid act more equally and allow the bubbles of gas to escape. The larger white parts are generally cut deeper afterwards with machine drills.
When other than transfers are to be reproduced, such as pen-and-ink drawings, engravings, or any other drawing in line, the subject is photographed to the required size. Here this process has a decided advantage over that just described, inasmuch as the drawing to be copied may be made of any convenient size, while a drawing on transfer paper must be of the exact size required. The photograph being obtained, it is treated as for a photolithograph (see LITHOGRAPHY), transferred to stone, and a re-transfer taken to put on the zinc, which is then treated as already described. By this process a little of the sharpness of the drawing is lost by the repeated transfers, every one tending to thicken and blur the lines a little; a more direct method of putting the drawing on the zinc is as follows. The plate is thinly and evenly coated with bitumen, dichromatised albumen, or other substance sensitive to the action of light. A very strong photographic negative, taken in reverse from the drawing, in which the lines are clear glass and the lights as dense as possible, is put on the plate and exposed to the light. The light acting through the lines on the negative render the corresponding parts of the coating on the zinc, to a sufficient extent, insoluble, while the light parts, being protected by the negative, can be dissolved out by a suitable solvent in the case of bitumen, or washed off if the albumen method is used. The drawing is thus left on the zinc in bitumen, and, as that substance is a good protective against acid, the plate is etched as already described.
There are also several gelatine processes, one or two of which may be shortly described. In the swelled gelatine process a plate of glass, coated with a film of dichromatised gelatine, is exposed under a negative, from a line drawing, and afterwards soaked in cold water, when the parts not acted upon by the light will swell up sufficiently to allow of a cast being taken which will give the lines in relief, or, if the plate be put in hot water, will be removed altogether, leaving the lines in relief. Or, if a photo-positive be put on the film, the lines will be left soluble and may be dissolved out by hot, or swelled up by cold water. In these gelatine processes, however, the relief is very low, and the white parts have to be made up with heated wax by hand, which is a very delicate process, or cut away in a subsequent stereotype. In some methods a solid slab of prepared gelatine is used, when the etching or dissolving out may be made as deep as required.
There are an infinity of other slightly differing processes for producing the same result, but as they are all more or less founded on the same principle, they do not call for separate description.
The production of relief blocks from ordinary photographs or drawings made by washes of black and white is a much more delicate matter. Intaglio plates have indeed been in successful use for many years (see PHOTOGRAVURE), but relief blocks until the invention of Meisenbach's process baffled all efforts. As in relief block every part which touches the paper prints black, and every part which does not touch the paper leaves it white, it is obvious that until some method was devised of turning the smoothly graded tones of a photograph into something which could be represented in pure black and white, success was impossible.
The method sought after was to break up the photo-tones into some sort of grain, stipple or line, which should be closest in the darkest parts, and become more open as the lights were approached. It would be unadvisable, even if it were possible, to enumerate all the devices which have been invented and patented for this purpose. That patented by Meisenbach of Munich in 1882, however, as the one on which nearly all the most successful subsequent processes are based, may be briefly explained. A glass plate is prepared with fine parallel lines, thus . This is exposed between the lens and the
sensitive plate in the camera, at a very short distance from the plate, and when the exposure is half completed the cap is put on the lens, the lined plate is taken out and put in with the lines in the reverse direction, thus
, and the exposure is completed. The resultant negative is thus broken into minute regular dots. These 'screens' are now prepared with cross lines, thus avoiding the necessity of changing the position during exposure. They are glass plates with etched lines, or are photographically printed from a plate so prepared—two plates being fastened face to face with their lines in opposite directions to give the cross effect. The lines may vary in width from 85 per inch for newspaper printing, to about 150 per inch for fine printing. Plates with 200 per inch produce work so very fine in grain that special printing is required.
A grained photograph being finally obtained by means of any of the thousand-and-one processes, it is transferred to zinc and etched as described for the line process.
In addition to these photo-chemical processes, there are several mechanical methods of producing relief blocks, of which Messrs Dawson's Typo-etching process, an improvement upon Palmer's (Glyphographic process (patented in 1848), is very extensively used for the production of maps, plans, diagrams, &c. A polished brass plate is covered with a film of prepared wax, on which the lines are drawn with special etching needles which clear away the wax down to the metal. Letters and words are stamped through the wax with types of varying sizes as may be required. The wax, which is of course very thin, is added to by melting other wax over the surface with a heated pointed metal tool. This stream of melted wax is skilfully prevented from running into the lines or letters, and when thick enough to give sufficient depth to the finished block, an electrotypic is taken from the plate, in which the cleared surface of the brass forms the raised lines, and the built-up wax the sunk or white parts. This electrotypic is the printing block. Many of the text maps in the present work are executed by this process; those in Vol. VI. p. 701, and Vol. VII. p. 762, are good examples.
Many other mechanical methods are used in engraving and etching, but generally they are too technical to be detailed here, and we have described nearly all which are of any public consequence.
It is obvious that these various processes, though simple enough in theory, give great scope for skill in manipulation, and much of their success depends on the ability of the operator. As a means of illustrating books they are making rapid strides towards complete success within the bounds, not by any means unlimited, of their capabilities. The rapidity with which they can be produced has rendered the daily illustrated paper a possible and accomplished fact. As to cost, blocks can be produced for from 4d. to 1s. 6d. per square inch of surface, according to the nature of the drawings—the stipple process being the more expensive.
The first and most important requisite is to obtain drawings suitable for the purpose, and these should be made by artists who have studied the capabilities and requirements of the various methods.
For the line processes the drawings, when not executed on transfer paper, should be made on bristol board or smooth-surfaced white paper, with some dense black pigment, as much of the success depends on the sharpness and blackness of even the faintest lines. Stephen's ebony stain, Winsor & Newton's liquid lampblack, and other pigments have been used for the purpose. The drawings should be larger than the required reproduction, as the reduction tends to refine the block, and care should be taken to see that every detail is exactly as wanted, for the process reproduces the defects as strongly as the beauties of a drawing. Given proper drawings and subjects suitable for the purpose, this process undoubtedly is capable of producing first-class work.
The stipple or Meisenbach process is a much more delicate affair, and from the care with which its blocks require to be printed, on account of the necessarily shallow nature of the etching, its application is much more limited. If nature photographs are reproduced on too small a scale, the stipple, if coarse, obliterates much of the detail, and, if too fine, is apt to blur in printing. But when drawings are specially made for it by artists who understand its requirements, it is capable of very fine results, and the drawing is reproduced with a fidelity seldom seen in an engraving. The drawings may be executed in lampblack and Chinese white, or any pure monochrome.
This process has been so improved and developed that it has become almost the universal medium for ordinary book illustration.
The weak point of nearly all tone-process work is that the sharpness and brilliancy of the original drawing gets softened and generalised away, and the result is sometimes flat and spiritless, with a tendency to become monotonous. The process has no white; even the highest lights are covered with tint. This difficulty is met by an increasing use of hand engraving on the blocks, in order to restore the vigour of the drawing, and to give something more or less like a good wood-engraving.
The latest development of the process is the Three-Colour Process. Coloured pictures, or naturally coloured objects, are by this method reproduced and printed by means of three blocks, printed with red, yellow, and blue inks respectively. It is founded on a suggestion by the late Clerk Maxwell, and Professor Vogel of Berlin and many others have helped in its development. By means of coloured screens, or light-filters, three separate negatives of the subject are taken, reproducing the colour values of the yellow, red, and blue rays respectively. These negatives are by the usual process made into blocks, which, if properly printed with the correctly coloured inks, produce a more or less exact facsimile of the original object or drawing. Many very fine examples of the process have been produced, in which every touch of the brush in a water-colour drawing has been faithfully reproduced. The care and delicacy necessary for successful printing, however, is very great, and the method should be limited to cases where specially prepared paper can be used in printing, or the result may be disappointing.
For purely photographic methods of illustration, such as collotype, see PHOTOGRAPHY.
See The Process Year-Book (annually); W. Savage, Practical Hints on Decorative Printing (Lond. 1822); Paper on Illustrated Books in Quarterly Magazine, vol. lxxiv. (June 1844); H. Bouchot, The Printed Book: its History, Illustrations, &c. (Eng. ed. by E. C. Bigmore, Lond. 1887; new ed. 1889); J. S. Hodson, Guide to Art Illustration (1884); Modern Methods of Illustrating Books (Lond. 1887); Joseph Pennell, Pen Drawing and Pen Draughtsmen (1889; new ed. 1894), and Modern Illustration (1895).