Authors: James Essinger
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The portrait of Jacquard was, in fact, a sheet of woven silk, framed and glazed, but looking so perfectly like an engraving, that it has been mistaken for such by two members of the Royal Academy.
Charles Babbage,
Passages from the Life of a Philosopher
,
1864
If you wanted to be part of the scientific and literary set in the London of the
1840
s, you would have done just about anything to beg, steal, or borrow an invitation to one of Charles Babbage’s famous soirées. Charles Babbage was a scientist, philosopher, engineer, mathematician, and writer. He had devoted much of his life to trying to build two types of calculating machines made out of cogwheels. He called these the Difference Engine and the Analytical Engine. So far he had failed to complete either of them, yet his struggle to do so had won him admiration even from people who were convinced his efforts were doomed to end in failure.
Babbage’s friends saw him as fascinating and brilliant. His enemies tended to think him moody, temperamental, and over-
(
left
) The Jacquard portrait.
Jacquard’s Web
rated. But even those who found him more irascible than inspired had to admit he gave splendid parties. These were held at his home: Number One Dorset Street. This is close to Manchester Square in the London district of Marylebone. Babbage’s soirées took place on Saturdays during the ‘season’, the time of the year when fashionable society would attend a whole range of gather-ings, dinners, and balls. The season usually lasted from late March until the end of July.
Babbage had moved to Dorset Street in
1828
. For the first few years his parties there were private functions for family and close friends. But in the early
1830
s he broadened the list of guests to include many of the leading luminaries of British intellectual life. During the next decade his social events became renowned throughout the capital. They frequently lasted until well after midnight, under the glow of thousands of candles.
Three hundred guests, or even more, might attend. Invitations were so prized that many of the most famous people in London used to write begging letters to Babbage to try to secure an invitation for themselves, their family, or friends.
The soirées eventually became one of the great rendezvous points for liberal intellectuals in Victorian London. Charles Dickens, Charles Darwin, Lord Byron’s daughter Ada Lovelace, the actor William Macready, the scientist Henry Fitton and his wife, the geologist Charles Lyell, the self-taught mathematician Mary Somerville and her family, the anatomist Richard Owen, the magistrate William Broderip, the astronomer Sir John Herschel; these are just a few of the ‘names’ who were often to be found at Babbage’s parties. An account by the American man of letters George Ticknor of a visit to one of Babbage’s parties on
26
May
1838
gives us a glimpse of what they were like: About eleven o’clock we got away from Lord Fitzwilliam’s and went to Mr Babbage’s. It was very crowded tonight, and very brilliant; for among the people there were Hallam, Mil-man and his pretty wife; the Bishop of Norwich, Stanley, the 2
The engraving that wasn’t
Bishop of Hereford, Musgrave, both the Hellenists; Rogers, Sir J. Herschel and his beautiful wife, Sedgwick, Mrs Somerville and her daughters, Senior, the Taylors, Sir F. Chantrey, Jane Porter, Lady Morgan, and I know not how many others.
We seemed really to know as many people as we should in a party at home, which is a rare thing in a strange capital, and rarest of all in this vast overgrown London. Notwithstanding, therefore, our fatiguing day, we enjoyed it very much.
Babbage delighted in entertaining the guests who came to his soirées with ingenious devices and gimmicks. In
1832
, having after a decade’s struggle finally managed to build one-seventh of the mechanism of the Difference Engine, Babbage proudly mounted the completed portion of the machine in a case of mahogany and glass. For eight years it was the most prominent conversation piece at his glittering events.
Then, in the spring of
1840
, Babbage started exhibiting something else.
On the face of it, this new exhibit was nothing more than an unassuming portrait of an inventor in his workshop. The portrait shows the inventor sitting in a luxurious cushioned chair at his work bench. He is holding a pair of callipers against long strips of cardboard that have tiny holes punched in them. The bench also accommodates a model of a loom. Hanging upon a rack on a wall behind the inventor are chisels and other tools in a variety of shapes and sizes. Rolled-up plans are poking out of a drawer on a table beneath the rack.
The portrait gives the impression of being an informal snap-shot of the inventor as he momentarily turns away from his work and glances at the artist. He has a thoughtful, frowning air about him, and his well-cut coat and general air of prosperity suggest that this is an inventor who has enjoyed some success.
Anybody giving the portrait a cursory inspection would assume that it is an engraving. This is exactly what the vast 3
Jacquard’s Web
majority of Babbage’s guests thought when they first set eyes on it. Babbage, a wily old fellow who took as much delight in exposing the errors and folly of his friends as he did in advancing the cause of science, enjoyed showing the portrait to his guests. He would then ask them how they thought it had been made. When they told him they were sure it was an engraving, as they usually did, he gave a knowing smile.
One evening in
1842
, two of the most distinguished people in the realm attended a soirée. They were the Duke of Wellington and Prince Albert, Queen Victoria’s husband. The ‘Iron Duke’ was the hero of Waterloo and a former Prime Minister.
Prince Albert was famous for his intellect and for the important, even essential, role he played in governing Britain. Officially he had no power, but in practice the Queen deferred to his judgement and opinion on almost every matter. She usually succeeded in persuading her ministers to do the same.
Almost as soon as the Duke and the Prince arrived, Babbage showed them the portrait. The Prince asked Babbage why he thought the portrait so important. Babbage replied, in characteristically enigmatic fashion, ‘It will greatly assist in explaining the nature of my calculating machine, the Analytical Engine.’
Once the two guests had examined the portrait, Babbage asked them what they thought it was. The Duke of Wellington, getting things wrong for once, made the usual mistake of responding that it must be an engraving. But it turned out the Prince knew the truth, having apparently heard of the portrait before. He informed the Duke of Wellington that the portrait was not an engraving at all, but a
woven piece of fabric
.
And the Prince was absolutely right. The picture was, in fact, a woven silk image. It depicts a French inventor named Joseph-Marie Jacquard. He had died six years earlier, on
7
August
1834
.
It was Jacquard who had invented the very loom on which the portrait was woven. This, the Jacquard loom, was the world’s first automatic machine for weaving elaborate and beautiful images into silk.
4
The engraving that wasn’t
The portrait, deliberately designed to illustrate and show off the Jacquard loom’s capabilities, is so complex it contains
24 000
rows of weaving. Every single row was controlled by what was in effect an early nineteenth-century programming device—a punched card. The
24 000
cards gave the loom precise instructions for weaving the portrait. These punched cards lie at the heart of Jacquard’s brilliant concept of an automatic loom that weaves complex patterns and images.
The portrait was woven in Lyons in
1838
by a weaving firm named Didier Petit & Co. It was based on an oil portrait of Jacquard originally painted by a Lyons artist, Claude Bonnefond, at the time the director of the City’s school of Fine Arts. Bonnefond took care to give the punched cards a prominent place in the portrait.
A few originals of the woven portrait still exist today. There is one in the reserve collection of the Science Museum in London, although unfortunately the portrait is no longer on general display, for the Museum has temporarily slimmed down its history of computing exhibition as a preparatory step to planning a major new display on computing and communications. However, you can ask for permission to view the Jacquard portrait in the reserve collection.
As you gaze into Jacquard’s stern features, it is difficult to believe that this faded, rather small picture (it only measures
20
by
14
inches), can be an illustration of a technology, developed more than two centuries ago, that was to alter our world beyond recognition.
Yet who exactly
was
Joseph-Marie Jacquard? How did he come to invent a loom that could weave pictures? And how did his extraordinary idea lead to the global information revolution that is continuing to transform the world in which we live today?
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To call forth figures, flowers, or patterns of any other kind, different means are necessary.
Dionysius Lardner,
A Treatise on the Silk Manufacture, 1831
Our story begins with the discovery of silk. And, according to legend, the story of silk begins with a cup of tea.
One afternoon, sometime around the year
2700 bc
, the Chinese empress Si Ling-Chi was strolling around her garden. She chanced to pick a fuzzy white cocoon from her favourite mulberry tree. Taking it over to her tea-table, she started toying with it. Her fingers were clumsy; a moment later she accidentally dropped it into her hot cup of tea. Fishing it out, she discovered to her surprise that she could pull out a long strand of thread from the cocoon. She pulled and pulled; the strand grew longer and longer.
Si Ling-Chi had discovered silk. A natural fibre produced by most spiders and by many caterpillars, silk is created in particular abundance and strength by the silkworm, which is really a caterpillar and whose diet consists almost entirely of mulberry leaves.
7
Jacquard’s Web
Whether this story of the origin of silk is literally true or a myth concocted to flatter the empress does not really matter.
What is certain is that the properties of silk, and the secrets of its production, were first discovered in China about three thousand years ago.
Astonishingly, the average silkworm cocoon contains a single thread of silk that when fully unwound is often as much as a full kilometre in length. The discovery of silk, and the revelation that numerous threads could be unrolled from a cocoon, spun into a stronger thread and used to make a fabric, caused a sensation.
Never before had anyone known of a fabric so soft, strong, durable, as readily dyed, and yet so dirt-resistant. Silk appeared the ultimate luxury. Indeed, it almost seemed a minor miracle.
The Chinese zealously guarded the source of silk and its production for many centuries. They didn’t even start exporting silk until more than two millennia after they first discovered it. But, in around
140 bc
, the secret of silk-making spread to India as an inevitable result of the thriving trade in silk between that country and China. Yet more than six centuries passed before the mystery of silk production finally reached Europe, which had believed for many centuries that silk thread was simply picked from certain trees native to China.
In
ad 550
, two Persian monks who had lived as missionaries in China related the truth about the origins of silk to the Byzan-tine emperor Justinian I. A man who was used to being obeyed, Justinian ordered the monks to return to China and smuggle silkworm eggs to Constantinople. He also promised them a hefty financial reward if they were successful. The monks, now pretending to be missionaries when they were in fact engaged on the emperor’s mission, trekked back to China and did his bidding, concealing thousands of silkworm eggs in the hollows of their bamboo canes.
Silkworm eggs enter a state of suspended animation when kept in the cold and dark. Once the eggs reached Constantinople, they were placed on top of a pile of warm manure and in 8
A better mousetrap
the sunshine. In these favourable conditions the eggs soon hatched. The emerging larvae were fed on leaves of the wild mulberry that grew abundantly in and around the city. The hardy silkworms resulting from this cunning act of industrial espionage gave birth to the European silk-making industry.
Homo sapiens
is believed to have first evolved about
200 000
years ago. For almost all of this time, the new species clothed itself in skins and furs torn from the bodies of animals that had been slaughtered for food. The production of fabric began, by comparison, far more recently, at about the same time as recorded history.