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PART FOUR: COMMUNICATION AND CALCULATION
672
as Pliny’s Historia naturalis, first printed in 1469 and the earliest scientific
work of all to be printed, astronomy was the subject most treated, as it was
the area of science more advanced than any other. Early in the next
century technological books began to appear—on mining, the assay of
metals, glassmaking, distilling. In mid-century appeared books that were to
initiate profound changes in the way man thought of his place in the
universe—above all Copernicus’ De revolutionibus orbium coelestium printed in
Nuremberg in 1543. The book was joined by the periodical, as scientific
work gathered pace from the mid-seventeenth century, in order to report
progress more quickly and conveniently. The earliest of these periodicals
that is still current is the Philosophical Transactions of the Royal Society, which
began to appear in 1665.
The book was not of course a new medium: the printer took it over from
the scribe. But he did invent a new medium—the printed sheet, to advertise or
give information. The earliest surviving piece of printing, and also the earliest
piece to come from Caxton’s press, is of this kind. It was an indulgence, an
announcement that a pardon was available to those who undertook certain
good works. There flowered a whole variety of ephemeral printing that was to
be the lot of the jobbing printer.
During the sixteenth century the printers began to satisfy a growing
demand for up-to-date information and entertainment in a more suitable form
than the book. From hand-written news reports circulated by hand was born
the news-book and then the news-sheet. At first spasmodic—the earliest English
example provided an account of the Battle of Flodden in 1513—they became
regular and emerged as the first true newspapers with the publication of Aviso-
Relation oder Zeitung, edited in Prague but printed in Wolfenbüttel, and the
Relation of the Strasburg printer Johann Carolus, both in 1609. ‘Corantos’, as
they were called began to spread and the first appeared in England from the
press of Thomas Archer in 1621. These were in the form of newsbooks, but


around mid-century the handier news-sheet emerged, among the earliest being
the London Gazette of 1665, still with us today. At the same time, the periodical
began to serve a desire for more leisurely background reading; the aim was
well expressed in the cumbersome title of one example, started in Leipzig in
1688: ‘Entertaining and serious, rational and unsophisticated ideas of all kinds
of useful and agreeable books and subjects’. By the turn of the century the
newspaper and magazine were established institutions and made rapid strides.
With the introduction of the daily post from Dover to London in 1691,
bringing in foreign news each day, the daily paper became a practical
proposition. The Daily Courant in London in 1702 was the first. Meanwhile the
weekly journal developed into the organ for enlightenment and entertainment,
above all in the hands of Richard Steele and Joseph Addison with their Tatler
(1709) and Spectator (1711), which exerted an immense influence on eighteenth-
century reading. One of the most successful of these periodicals was the
LANGUAGE, WRITING, AND GRAPHIC ARTS
673
Gentleman’s Magazine (1731–1907), which reached a circulation of 15,000 in
1745 and gave the name ‘magazine’ to this type of production.
The enterprise shown by the printers, publishers and booksellers in
developing this remarkably wide variety of reading matter was in striking
contrast to the conservatism of their technology. The earliest illustration of a
press is a rather crude woodcut of 1499, the ‘Dance of Death’ print from
Lyons. The equally well-known Badius prints of 1507 and 1520 provide a
better idea of an early press room. Yet the first detailed account in any
language did not appear until 1683–4 in Joseph Moxon’s Mechanick exercises on
the whole an of printing. Clearly little had changed and Moxon’s work served as
the basis of later handbooks throughout the age of hand printing. A few
components were made of iron, but wood remained the principal material,
above all for the frame. That restricted the total load that could be imposed by
the platen upon the bed of the press and that meant that only half a sheet

could be printed at one pull. Production is said to have attained 250 sheets an
hour, but that was doubtless an upper limit rather than an everyday average.
Towards the end of the sixteenth century, the composition of the type-metal
was changed slightly to give greater toughness to withstand the longer print
runs that were becoming the rule. As to the paper, once mediaeval Europe had
made slight modifications to the materials and techniques received from the
East, there was little change until the Industrial Revolution. The raw material
was rag, usually linen, and this was cut up into small pieces, boiled, allowed to
ferment to assist disintegration and finally subjected to the action of wooden
stampers. That completed the separation into fibres which, mixed with water
to the consistency of thin porridge, formed the ‘stock’ from which the paper
was made. The papermaker dipped into the pulp his mould, consisting of a
rectangular wooden frame with a mesh of closely spaced brass wires and
heavier wires at right angles more widely spaced. The size of the sheet was
determined by a second frame, or deckle, placed over the first. When he had
scooped up an even layer of pulp on the mould, he gave it a shake to help
interlock the fibres and release some of the water. He had made a sheet of
paper. The rest of the process, then as now, consisted of getting rid of the rest
of the water. The mould wires gave rise to the characteristic wire and chain
marks of hand-made paper, although Whatman introduced ‘wove’ paper in
1757, using a mould with woven wire to produce a smooth surface.
Stamping was mechanized and water-powered during the thirteenth century
and this stage of the process was greatly accelerated around 1650 by the
invention of the hollander, a vessel in which a vertical spindle with knife blades
rotated to lacerate the rags.
Book illustration had settled into a rut. During the early period woodcuts
were used, the raised portions receiving the ink with the type, so that text and
illustration could be printed together. But towards the end of the sixteenth
century, the copper engraving began to supplant the wood block, on account
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674
of the finer detail that could be reproduced. In this intaglio process, the ink was
received by lines incised into the metal and a sheet of paper in contact with the
plate was forced through an engraving press, rather like a mangle. The
illustrations thus had to be printed separately from the text and were on sheets
interspersed throughout the text or gathered together at the end. Only in
recent years has a reconciliation between text and illustration been effected by
modern offset litho printing.
TECHNOLOGICAL INNOVATION IN THE
NINETEENTH CENTURY
Change, when at last it came, began in the country where the Industrial
Revolution had already begun to change so much: England. It revolutionized
not only the look and feel of the printed book but the reading habits of the
industrialized nations. The move to mechanize paper production began with
the making of a model papermaking machine by Nicolas Louis Robert in 1797
at a mill in Essonnes, south of Paris. After applying for a patent the following
year, Robert fell out with his backer and owner of the mill, Didot, although the
latter did contact John Gamble in England to see if capital could be raised
there for a full-sized machine—all this against the background of the
Napoleonic Wars. Gamble and the London stationers the brothers Fourdrinier
called in the engineer Bryan Donkin and in 1807 they patented a much
superior version of Robert’s invention. Pulp passed over a ‘breast box’ in a
continuous stream on to a wove-wire screen. The fibrous sheet was passed
between rollers to remove some of the water. The paper was then transferred
to a felt blanket and a second pair of rollers to remove more water and finally
wound on to a drum while still quite wet. Steam-heated drying cylinders were
introduced by Thomas Crompton in 1820 and at last it was possible to
produce a continuous sheet or web of dry paper. Later, detailed modifications
were made to improve quality and widen the range of papers available, but the
modern machine, although much larger and faster, operates on the same

principle as the early Fourdrinier examples. Even those early machines were
able to raise production from the 25–45kg (60–100lb) a day of the old manual
process to 450kg (1000lb) a day with a corresponding reduction in cost to the
customer. This development was well timed, as the improvements in the
printing press that were about to take place would have been useless unless
paper production had kept pace.
The first major change in the press was brought about by Charles Mahon,
3rd Earl Stanhope, who in 1800 introduced the first successful iron press, the
famous Stanhope press. The iron frame not only enabled the whole forme (the
frame containing the body of type for a complete sheet) to be printed at one
pull, thus speeding up production, but larger formes could be handled without
LANGUAGE, WRITING, AND GRAPHIC ARTS
675
straining the frame. While retaining the screw-operated platen (the plate which
pressed the type against the paper), a system of levers attached to the bar
increased the pressure at the moment of contact. This gave beautifully sharp
impressions on the paper and also eased the strain on the pressman.
Production rate rose to about 300 sheets an hour. The Times, soon to be and
long to remain in the vanguard of technical progress, was printed on a battery
of Stanhopes during the early 1800s.
A number of improved designs of iron hand-press soon followed, the most
celebrated being the American Columbian press, invented by Floyd Clymer in
1813. The screw device was replaced by a system of levers assisted by a
counterweight in the form of a gilded cast-iron eagle, which gave the press its
characteristic flamboyant touch. Many of the masterpieces of nineteenth-
century literature were printed on such presses—most book work until mid-
century and much thereafter flowed from them—but they could not meet the
needs of the newspaper proprietors.
The first machine press was invented by Friedrich König and Andreas
Bauer of Würzburg in 1811. As the German engineering industry was not

sufficiently well developed to manufacture their invention they moved to
England and their first successful press was patented in 1812. A revolving
cylinder carried the paper, which received an impression from a reciprocating
bed carrying the type forme. The machine could be operated by hand but
steam power could also be harnessed. The real breakthrough came when
König and Bauer constructed a twin-cylinder machine for John Walter of The
Times. On that famous night of 29 November 1814, behind closed doors to
avoid disruptive attentions from conservative-minded printers, a newspaper
was printed for the first time on a machine press. Production shot up to 1100
sheets an hour, but more was to come. After so many years of stagnation
progress now became rapid indeed. The Applegath and Cowper four-cylinder
press of 1827, made for The Times again, carried the rate up to 4000 sheets an
hour. Their type-revolving press twenty years later took it up to 8000. It was
the newspaper that led the demand for higher speeds and stimulated yet
further development.
The next stage was to replace the reciprocating flat-bed by a continuously
rotating cylinder press, carrying the type on a curved forme. The first press of
this kind was constructed by R.Hoe & Co. in 1846 for the Philadelphia Ledger
in the USA. The cylinder of this huge machine was about 2m (6.5ft) in
diameter and, with four impression cylinders printing off at four points around
the circumference, output attained 8000 sheets an hour. Even larger machines
of this kind followed, with ten impression cylinders giving 20,000 sheets an
hour. Paris received its first Hoe press in 1848 and London in 1856; The Times
ordered two of them.
The way forward to greater speed was to print on both sides of the paper at
once—a perfecting press—and on to a continuous web of paper instead of
PART FOUR: COMMUNICATION AND CALCULATION
676
separate sheets. The first to be constructed was the Bullock press in
Philadelphia in 1863 and five years later The Times built one, known as the

Walter press, after the then editor John Walter III. This could print 15,000
completed copies, or over 60,000 sheets an hour. The printing press thereby
achieved its final form; future developments were in size and greater speed
rather than in design principles. In the Bullock press the paper, although fed
from a reel, was cut up into sheets before printing; on the Walter press a
continuous web of paper was fed through, printed on both sides, separated
into sheets and copies delivered alternately to two delivery points.
The mass-circulation newspaper, springing up in the 1880s, called for yet
more speed and the Walter concept was refined, using several printing
formes to a cylinder, combining several cylinders in a machine (Hoe in 1882)
and then these were placed vertically. The first folding device was
incorporated in 1870. In 1920 the Goss Company introduced the Unit press
with several printing units placed in line and the webs from each gathered
together at one point for folding and cutting. From the early years of the
twentieth century steam or gas power gave way to electricity and the modern
high-speed press had arrived.
An essential element in the quest for speed was the rotary principle, by
which the type forme was curved to follow the shape of a cylinder, replacing
the flat forme on a flat-bed press. At first type was cast in wedge-shaped
moulds and clamped to the cylinders, but this led to problems with dislodged
type, so curved stereotypes were introduced. During the eighteenth century
attempts had been made to make a mould of a forme of type and cast a
printing plate from it to enable copies to be run off while the original type
was distributed for use of a fresh piece of work. William Ged, a Scottish
goldsmith, experimented with plaster moulds in the 1720s, but opposition
from the printers, who feared that the innovation would lead to loss of work,
put an end to these experiments. In France, however, contemporary work
along the same lines found a readier response, particularly in the making of
plates for printing currency during a period of high inflation. But it was
Stanhope’s second great contribution to printing technology to perfect a

method for making printing plates: stereotypes. Later the plaster moulds
were found to be heavy and fragile and in 1829 the French printer Claude
Genoux substituted papier mâché, known as wet flong. This in turn was
replaced by dry flong in 1893, paving the way for a mechanized process, the
Standard Autoplate Caster by Henry A.Wise Wood in 1900. Stereotypes for
rotary presses were of course cast in type metal in curved formes. Recently
modern materials have replaced metal for printing certain kinds of material,
such as synthetic rubber and plastics.
Not all printers demanded the high speeds required by the newspaper
proprietors. For book printing, let alone the miscellaneous work of the
jobbing printer, something more sedate was favoured, something the printer
LANGUAGE, WRITING, AND GRAPHIC ARTS
677
could feel was more like a hand-press. Indeed, the hand-press carried on for
much commercial book work well into the nineteenth century, but two types
of machine were developed to serve his needs: the cylinder and the platen.
William Rutt designed a small hand-operated press based on the König &
Bauer in which the impression cylinder came to rest after printing a sheet to
allow the flat bed carrying the type to be moved back to the starting position.
This showed no saving in time over the hand-press, but the Naypeer of 1824,
developed by David Napier and commissioned by T.C.Hansard for book
printing, was more successful. By 1830, the machine had incorporated two
important advances: gripping fingers on the cylinder to take a sheet of paper
through the machine, enabling the sheet to be accurately placed on the
cylinder; and a continuously revolving cylinder, rising to allow the bed to
return after each impression. Between 1830 and 1860 many patents were
taken out for cylinder presses. The best known was the Wharfedale, from
the name of the valley in Yorkshire where Otley, its place of origin, is
situated. Developed by Dawson and Payne in 1859, it was of the stop-
cylinder pattern and of robust construction. Similar machines were made in

other countries and the name Wharfedale became the generic term for this
veritable workhorse of the industry for many years. The version
manufactured by König & Bauer in Würzburg in the early years of the
twentieth century could print 1200 sheets an hour.
Even that was too elaborate for the jobber and the platen press was evolved
to serve his needs. A foot-operated press was patented in London in 1820 by
the appropriately named American inventor Daniel Treadwell, but it did not
succeed. Other American inventors took up the idea and the Ruggles press of
1851 set the pattern, with a vertical type bed against which the paper-bearing
platen closed. This was followed by Gordon’s Franklin press in 1856 which
became the general form for small jobbing platen presses. When small electric
motors to work such machines became available in the early 1900s (see
Chapter 6), automatic paper-feed was added and the field was dominated by
the Heidelberg and Thompson platens until this kind of press began to be
superseded by the small office offset litho machine in the 1950s.
The Fourdrinier papermaking machine, the power-operated rotary, cylinder,
and platen presses, and the stereotype, made possible the mass dissemination
of literature of all kinds. There was the improving literature promoted by such
bodies as the Society for the Diffusion of Useful Knowledge founded in 1826
with such notable publications as the Penny Magazine and Penny Encyclopaedia
founded in 1832 and 1835 by the great popular educator Charles Knight.
They made possible a wide readership for Dickens’s bestsellers; they also
produced a flood of cheap trash. The Industrial Revolution had helped to
bring about a desire for both educational and entertaining reading matter
among the artisan and new rising middle classes, but it was the technical
advances that led the revolution in reading habits of the masses.
PART FOUR: COMMUNICATION AND CALCULATION
678
The copper engraving had by 1800 done yeoman service for centuries, but
copper is a soft metal and ill-suited to the wear imposed by long print runs.

Steel engraving, begun in the USA in 1810 for bank notes, spread to Europe
and soon superseded copper, thus helping to bring down the price of illustrated
books and place them within reach of the masses. The wood engraving was
also a popular medium, brought to perfection by Thomas Bewick. Here, the
wood block was cut across the grain instead of with it, as for earlier wood cuts,
and finely engraved illustrations could be made cheaply and quickly, retaining
quality after long print runs. They made possible cheap illustrated magazines
like the Penny Magazine, the Illustrated London News (1842) and Punch (1841).
For higher quality work, such as art reproductions, the mezzotint and
aquatint gave good results. Mezzotints are a kind of engraving in which the
metal plate is roughened with a ‘rocker’ with a serrated edge. The areas
corresponding to the lighter parts of the picture are then smoothed with a
scraper to a varying degree. Aquatints are produced by etching the metal plate,
that is, eroding it with acid, through a porous ground. The lightest portions are
then etched and given a varnish coating to protect them from further action of
the acid. Darker areas are then formed by successive etching and varnishing.
By these means, subtle gradations of tone can be produced. Mezzotints were
used mainly for reproducing paintings and portraits, aquatints for
topographical scenes and descriptive illustations.
Both methods were supplanted by lithography, invented by happy accident
by Johann Alois Senefelder of Munich when he found that after marking the
flat surface of a piece of limestone with a greasy crayon, dampening the surface
and passing an inked roller over it, the ink covered the greasy marks but was
rejected by the rest. If paper was pressed on to the surface, it took up the image
in reverse. Senefelder began to use lithography (‘stone printing’) in 1800. He
tried unsuccessfully to keep the process to himself, publishing no account of it
until 1818. The following year Ackermann brought out an English translation,
A Complete Course of Lithography, and from 1830 lithography had virtually
triumphed for printed illustrations, except for mezzotints for paintings, steel
engravings for cheap books and wood engravings for both popular periodicals

and books.
A slab of limestone had certain disadvantages; it was cumbersome and
broke if handled clumsily. Metal plates were sometimes used instead—zinc from
around 1830 and aluminium became a practical proposition in 1904. The
versatility of the process was greatly increased by the offset principle, first used
to print on to tinplate. The hard unyielding printing surface was replaced by a
resilient rubber surface by transferring or ‘offsetting’ the image from one to the
other and then printing on to the tin surface. Robert Barclay patented this
process in 1875 but printing on to paper had to await the development of a
suitable rotary press for offset litho printing, by Harris in the USA and George
Mann & Co. in Britain in the early years of this century.
LANGUAGE, WRITING, AND GRAPHIC ARTS
679
For much of the nineteenth century, the great mass of the printed
illustrations produced required the services of armies of artists, whether for
‘artistic’ work or for purely factual representation for instruction purposes or
news media. The invention and development of photography from the late
1820s (see p. 731ff.) provided a method of factual representation, but the large-
scale mechanical reproduction of photographs was not easy: it was not until
the 1880s that a photo-process engraved plate, that could be printed in a press
like a hand-engraved one, became a possibility. The Daily Telegraph in 1882 was
the first newspaper to use photographic line blocks, known as zincographs
because sensitized zinc plates were used, while the Daily Graphic was the first to
publish such illustrations in bulk. So far only the lines in a photograph could
be printed. The breakthrough to reproducing the whole range of tones was
achieved with the invention of the half-tone process. The original was copied
by a process camera in which a cross-line screen was interposed in front of the
negative, producing a photograph consisting of thousands of dots which,
viewed from a distance, gave the illusion of tone variation. From the ‘dotted’
negative, a ‘dotted’ sensitized printing plate was prepared, which could be

printed off with the rest of the text. The use of half-tone blocks in newspapers
dates from 1877 by the Jaffé brothers in Vienna, taken up by Horgan in the
USA with the New York Daily Graphic in 1880. The London Daily Graphic was
using them in 1894 and the daily newspaper illustrated by a new breed, the
press photographer, was in being. Harmsworth’s Daily Mirror, starting in 1903,
the first newspaper to be sold at a halfpenny, epitomized the new mass
journalism, made possible by rotary press, papermaking machine, stereotype
and half-tone block.
Another way of mass-printing photographs has been photogravure, an
engraving or intaglio process. Artists had for centuries graved in copper plates
lines that held the ink, which was transferred by pressure to the paper. In 1879,
Karl Klic exhibited plates derived from photographs. The ink was held in a
myriad of minute cells in the surface of the plate, of varying depth according to
the tones of the original. Klic next developed a gravure cylinder for use in a
rotary press. The cylinder dipped into free-flowing ink which was then wiped
off by a ‘doctor’ blade, leaving the ink in the cells.
With all this plethora of progress in nineteenth century printing technology,
one process remained obstinately at the primitive, hand-worked stage—
typesetting. The making of the type was successfully mechanized as early as
1838 with the Bruce typecaster, developed by David Bruce in the USA, using a
pivotal action of the mould to and from the mouth of a hot-metal pump. It was
exhibited in London at the Great Exhibition of 1851 and its use became
widespread in Britain soon afterwards. The Wicks caster of 1878, producing
complete sets (founts) of type could turn out some 60,000 types an hour. But
every letter to be printed still had to be taken out of the type case by the
compositor, placed in his hand-held composing stick and transferred to the
PART FOUR: COMMUNICATION AND CALCULATION
680
galley in batches to be made ready for printing. After printing, each type had
to be returned to its place in the type case. A veritable army of compositors

was needed to satisfy the voracious appetite of the rotary presses. Many
inventions were devised to mechanize this process, but none was really
satisfactory. The first approach was to assemble and distribute the types
themselves mechanically. The first record of such a machine is of that patented
by the London-based New Yorker Dr William Church in 1822, but it seems
never to have been constructed. Many later forms were tried and some gave
useful service, but none was at the same time reliable and mechanized the
whole process. One of the most successful was the Kastenbein, used by The
Times for many years. Here, the type was assembled mechanically for printing
and melted down after use; a fresh fount of type was then cast by a Wicks
caster. The problem was solved by following a different route— assembling
moulds or matrices of the required characters, casting the type and returning
the matrices to their original positions ready for use again. It was a
Württemberg watchmaker and immigrant to the USA, Ottmar Mergenthaler,
who achieved the breakthrough with the Linotype machine, which produced
casts of slugs, or complete lines of type. The first model was completed in
1885 and was first used in the office of the New York Tribune the following year.
An improved model came out in 1890 and hundreds were constructed for sale
in the USA, Great Britain and later in Europe. By 1900, 21 London dailies
were being set on the Linotype.
At much the same time, in 1887, the Monotype machine was developed by
the American Tolbert Lanston. Its keyboard unit produced a strip of paper
tape with holes punched in patterns corresponding to the characters required
and this controlled the assembly of matrices in the caster, from which types
cast singly were ejected and fed to an assembly point until a complete line had
been formed. It became a commercial proposition in 1894 and an advanced
model was installed by Cassell & Co. in London in 1900. Some hand setting
carried on until the First World War, but from the 1920s Monotype and
Linotype reigned supreme—the former mainly for book work, the latter for
newspapers.

For the first half of this century hot-metal type setting and relief (letterpress)
printing produced the vast majority of the public’s reading matter. For long
runs of illustrated magazines gravure printing was more suitable. The Illustrated
London News was the first in which pictures and text were printed
simultaneously by gravure, from 1913. This process has still not entirely given
way to offset lithography for the ‘popular illustrateds’.
For half a century printing seemed quite settled in its hot-metal, letterpress
ways and few would have predicted that in a relatively few years a revolution
in technology would sweep aside these time-honoured processes and almost do
away with metal type. The new photocomposing process was envisaged in
patents even in the nineteenth century and inventors were seeking ways of
LANGUAGE, WRITING, AND GRAPHIC ARTS
681
dispensing with metal types in the 1920s, but it was not until after the Second
World War that commercially practical machines became available.
Photocomposing began to be used more widely after improvements in
lithographic printing were made and quicker, cheaper methods were found of
making letterpress printing blocks from photographs. In the 1950s some hot-
metal machines were adapted to become photosetters by replacing the matrix
with a photographic negative. Meanwhile, a new range of specially designed
machines, such as the Lumitype of French origin, was being developed, in
which the keyboard produced a punched paper tape with coded instructions
for operating a photographic printer.
Computers were introduced in order to decide about line length, justifying
the right-hand margin, spacing between words and so on, decisions previously
taken by the compositor. Two kinds of photosetter emerged, one where the
keyboard generated a paper or magnetic tape that controlled the operation of
the photo-matrix and one where the operator controlled this direct. A beam of
light created the images of the characters on the photographic film or paper.
The next stage used a system of electronics to build up the images of the

characters in a cathode-ray tube, as in the Linotron 505. Beyond that, the
character image could be stored in the form of magnetic impulses in a
computer (digital storage), cutting out the need for a photographic matrix.
Here, we have reached the stage where a reporter with a keyboard unit can
generate impulses through a telephone line and the computer-controlled
photosetter can produce the copy from which, via a process camera, a printing
plate can be made for printing by offset lithography. This method dispenses
not only with metal type, but with the compositor himself. The printing
industry has traditionally viewed technical advances with suspicion,
understandably when they cause job losses, and the new computerized
photosetters have certainly met their share of opposition. But, properly
managed, the advance has been beneficial and hot-metal technology belongs to
the past.
COLOUR PRINTING
The nineteenth century also saw the flowering of colour printing. Until that
time, nearly all the colour that appeared in books was applied by hand, but
then several processes were developed for colour printing on a commercial
scale. They all, like the Baxter prints and chromolithographs, entailed
repeated printing in exact register of each colour that constituted the final
picture, a laborious and expensive procedure. Technical progress in this field
depended on a proper understanding of the theoretical background of the
nature of colours and how they could be produced by mixing the three
primary colours, red, blue, and yellow. Some progress was made in applying

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