Madder is indigenous to western Asia, and was introduced to Spain by the Moors. It was widely used in Holland in the sixteenth century, and in Avignon a century later. Its use as a dye, on textiles and occasionally ceramics, has been described by Pliny the Elder and in the Talmud. In 1809 the French chemist J. Chaptal detected a pink pigment he had found in a shop in excavations at Pompeii that may have come from a madder lake. In 1815 Humphrey Davy found a similar colour, probably from a similar origin, on a broken ceramic vase at the Baths of Titus. In the seventh century, textiles dyed with madder were sold at St Denis near Paris, and Charlemagne is known to have encouraged its growth. Vegetative remains of madder were found in excavations from the tenth century in York. As recently as 1993, the conservationist J. H. Townsend identified madder lakes in palettes used by J. M. W. Turner.
But chemistry believed that the Turners of the future would paint just as well with acrylics. On 8 May 1879, Perkin addressed the Society of Arts in London on his efforts to eliminate the need for ancient madder and synthesise its tinctorial properties in a factory. There was little remorse for the erosion of an age-old natural trade, but he did exhibit a great understanding of the traditional methods of cultivation and dyeing.
‘The time from planting until the roots are drawn is from eighteen to thirty months,’ he told his audience. ‘When dried, the roots lose their reddish yellow colour and become of a pale red shade. The process of drying is conducted in the air or in kilns. When dry, the roots are beaten to remove sand, clay and loose skin …’
Depending on the mordant and strength of dye, the textile shades ranged from pink, red, purple and black. Another tint, a brilliant and strong red known as Turkey red or Adrianople red, required a cotton mordant of olive oil, and the addition of a little animal blood.
But what of the colouring matter within madder which rendered it so desirable? Little was known of it until 1827, when two Frenchmen, Colin and Robiquet, introduced a method of producing garancine, a concentrated form of natural madder, and at the same time detected precisely what it was that gave the root of the plant its value. By heating ground madder in a test tube with various acids and potash they obtained a yellowish vapour which crystallised into bright red needles. They called this substance alizarin, from the Levantine term for madder, alizari.
Alizarin made up only about one per cent of the madder root, and colour chemists reasoned that – as with magenta and cochineal – finding the correct molecular constitution for alizarin would yield a far greater purity and efficiency, and some riches. A Manchester-born calico printer named Henry Edward Schunck spent much of the 1840s and 1850s investigating the madder root, believing that any artificial formulation would require a similar naphthalene base as previous synthetic colours. Like Perkin in his early days, his chemistry was largely empirical, and still involved an often fruitless trial-and-error process of adding or subtracting a variety of carbon and hydrogen elements and hoping for success.
But the nature of molecular understanding was changing rapidly. In 1858, Friedrich August Kekulé had explained the concept of isomerism (the presence of compounds with the same molecular formula but different arrangements of the atoms within the molecule). Yet Kekulé’s groundbreaking Theory of Molecular Structure failed to explain the behaviour of benzene, the hydrocarbon present in coal-tar and known as an ‘aromatic’ compound because of its presence in scented oils. The answer appeared to him one evening while he was dozing in front of a fire, a vision of gambolling atoms in snake-like motion. ‘One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes.’ In this way he reasoned that carbon atoms formed rings: his benzene structure consisted of six carbon atoms, each attached to a hydrogen atom (C6 H6)
The analysis of chemical structures would now proceed on a more rational basis. Hofmann had already been able to define the chemical formula of fuchsine, and now was able to resolve its precise elemental formula. Two other chemists who made full use of this new knowledge also worked in Berlin – Carl Graebe and Carl Liebermann. In 1868, they demonstrated that alizarin did not have a naphthalene base but one of anthracene, another aromatic compound present in coal-tar. Graebe and Liebermann showed that anthracene consisted of three fused benzene rings, and they were thus able to synthesise alizarin in the laboratory – the first time a vegetable colouring matter had been made in this way – and they patented their discovery in December 1868. Unfortunately, their vastly complex method involved the use of prohibitively expensive and volatile liquid bromine in small sealed tubes, and they were unable to produce alizarin on any scale. To this end they enlisted the services of Heinrich Caro, the skilled industrial chemist who had returned to his homeland in 1866 after obtaining great practical experience in Manchester. Caro had returned to study and teach at the University of Heidelberg, but soon landed the job of director of research at BASF, Germany’s largest dye factory. No one employed at these works underestimated the value of being able to produce alizarin in giant vats; demand appeared to be insatiable. But they soon discovered a rival.
William Perkin was ideally placed to exploit the situation. Not long after he had joined the Royal College of Chemistry in his teens, August Hofmann had instructed Perkin to prepare and examine anthracene from coal-tar pitch. As Perkin remembered at a memorial after Hofmann’s death, he was perhaps ‘more fully prepared than any other chemist of the day to appreciate the discovery of the relationship of alizarin to, and was naturally impelled at once to adapt it to practical requirements’. With mauve no longer in vogue and the price of magenta tumbling due to widespread competition, the possibility of adapting his Greenford Green works for the large-scale manufacture of alizarin presented a breathtaking challenge. Alizarin was not prone to the vagaries of fashion; unlike mauve or some of the aniline dyes that followed it, dyers did not need persuading of its usefulness or instruction as to its application. In Scotland alone there were more than seventy dye works keen to take out orders.
Within a year, William Perkin and his brother had devised two processes by which alizarin might be manufactured, and neither required the use of bromine. Initially, Perkin & Sons (the plant retained the name after their father’s death) experimented with the original anthracene left over from Perkin’s student days, and began a series of combustions. The most successful entailed heating anthraquinone (another aromatic benzene-like compound present in coal-tar) with sulphuric acid, the product then fused with caustic alkali. ‘To my delight [the result] changed first to violet, and then became black from the intensity of its colour. On dissolving the melt, a beautiful purple solution was obtained, which gave a yellow precipitate when acidified, and on examination was found to dye mordanted cloth like garancine.’
As he did with mauve, Perkin sought the opinion of an experienced dyer, again in Scotland. On 20 May he sent samples to Robert Hogg in Glasgow, an expert in madder, who told him that the quality was superb. Perkin then sought a patent, noting later how ‘this process has proved the most permanently important one yet discovered.’ He began to gear up for mass production.
With their earlier colours no longer in great demand, the Perkins found they could adapt some of their existing apparatus for alizarin, but they also needed to expand. A new plant was planned, and new staff hired. Again, they faced many supply problems of key ingredients, not least with anthracene; tar distillers had previously found no use for it and failed to produce it. The first quantities were made on site by distilling tar pitch, but, as Perkin later recalled, it was necessary for his brother to visit ‘nearly all the tar works in the kingdom’ to show distillers how to separate anthracene. Other problems – the purification of the anthraquinone, the transport from Germany of fuming sulphuric acid – required the Perkins to alternate between two different production processes, and revert to some unorthodox methods. The compounds were combined in a large bath, before being placed in a revolving cylinder into which cannon balls were added to improve mixing. Another difficulty concerned pricing.
Unlike many of the previous dyes, for which there was no direct natural competitor, madder had a fixed and competitive cost structure, and Perkin & Sons had to ensure that its production was of such a scale and efficiency that they could undercut the present price levels of 50 shillings per hundredweight for madder and 150 shillings per hundredweight for garancine.
But then they were hit by another problem, something that threatened the entire business. Perkin’s patent for his first alizarin production process was granted on 26 June 1869, but the patent application for a very similar method had been filed just the day before by Graebe, Liebermann and Heinrich Caro of Berlin. Initially, Perkin was devastated, not least because Caro was a friend of his.
Some years later, Perkin would cite the inexact and lumbering workings of the British patent office as a great hindrance to industrial progress, but at the time of the alizarin dispute he limited his public frustration to a footnote on a paper he delivered to the Society of Arts. He noted that Graebe and Liebermann claimed that Heinrich Caro had formulated the process before Perkin, and that ‘if any particular importance is attached to dates, the advantage rests without dispute with Caro, Graebe and Liebermann, for the filing of the patent … was delayed through irregularity. The signatures had already been given in to the Patent Office, Berlin, on the 15th June.’ Perkin fumed: ‘I may remark, in reference to the first statement, that Graebe and Liebermann neither give or adduce any evidence to substantiate their claim to priority.’ He confirmed that his dyed pattern samples had been sent to Robert Hogg several weeks before the dates in question, and that his patent had also been delayed. ‘Therefore, their conclusions, from the argument as to dates, should be reversed … Without wishing to detract from Graebe and Liebermann’s original discovery, we may say that the birthplace of the manufacture of artificial alizarin was in England.’
In the end, both patents were granted. The BASF patent was registered one day earlier, but Perkin’s was sealed first. Perkin invited Heinrich Caro to Greenford Green to carve up their markets, and it was agreed that Perkin & Sons should hold the British monopoly for several years while BASF controlled the market in mainland Europe and the United States. The first shipments of artificial alizarin left Harrow on 4 October 1869, and by the end of the year one ton of paste had been made. Production at BASF had been held up due to the Franco-Prussian war, and Perkin found that he had the world market to himself for almost a year. ‘In 1870 we produced 40 tons,’ Perkin noted. ‘In 1871, 220 tons; in 1872, 300 tons; and in 1873, 435 tons.’
In the first year of production, William Perkin received some correspondence which suggested that he had not made alizarin at all; it was claimed that the fiery qualities of his colours had never been produced from natural madder: ‘The red shades were more brilliant and more scarlet, and the purples bluer; the blacks were also more intense.’ In May 1870 Perkin felt impelled to demonstrate to the Chemical Society that alizarin could indeed be separated from his commercial product, and that it possessed the same dyeing properties as the natural root.
The financial rewards were great, despite tumbling prices. Perkin & Sons received approximately £200 per ton. By the end of the 1870s this had fallen to £150 per ton, or about one-third of the price of natural madder in 1868. In the two years before June 1873, Perkin & Sons made an annual profit of about £60,000. William Perkin’s personal fortune was approximately £100,000, precisely the figure Victorian businessmen used to denote a man of substance.
At the height of his achievement, Perkin addressed the Society of Arts about the ‘wonderful’ and staggering growth of the coal-tar colour industry. Omitting his personal role in the enterprise, he spoke of how the industry had ‘acted as a handmaid to chemical science, by placing at the disposal of chemists products which otherwise could not have been obtained, and thus an amount of research has been conducted through it so extensive that it is difficult to realise, and this may, before long, produce practical fruit to an extent we have no conception of.’
But the fruits would not reside predominantly in Britain. In 1878 the estimated value of coal-tar production in England stood at £450,000, compared to £350,000 in France and Switzerland, and £2 million in Germany. This was only the beginning of Germany’s dominance. A year later, there were seventeen coal-tar colour works in Germany, compared with five in France, four in Switzerland and six in England. Perkin & Sons was no longer among them.
*
In October 1999, a 47-year-old man called Robert Bud sat in his office at the Science Museum in London, and explained how he had once designed the museum’s modest display on artificial dyes. A large, roundish man with short brown curly hair, Bud had been at the museum for twenty-one years and was now Head of Research (Collections). He also had a responsibility for organising conferences: his computer hummed with e-mails about a conference he was planning for July 2001 on Victorian culture. By July 2001 it would be 150 years since the Great Exhibition, 100 since the death of Victoria herself. He produced an early leaflet about the conference and said of its colour: ‘It was the closest we could get to the original mauve.’
His office opened onto a stairwell, and from this another door led directly to the chemical industry section of the museum. It was shortly after 9 a.m.; the place was not yet open to the public, but the working displays were already grinding away. Dr Bud walked a few yards to the exhibits about dyes, a series of models and cases and backboards he helped construct thirteen years ago.
He touched a huge wooden dye vat from an ICI plant in Blackley, near Manchester, which until 1980 was used for making detergent. It still had that smell. ‘Sulphuric acid was added to fish oil and salt water,’ he said. ‘Very crude, very simple, very typical. The chemistry was very sophisticated, but the technology was often not.’
There are four elements of Bud’s dyeing display: the vat, three mannequins wearing clothes from the 1880s, 1930s and 1960s, a portrait of Perkin with a model of a man called Rudolph Knietsch (one of the developers of synthetic indigo) in front of him, and a glass case opposite containing bottles of powdered dye and a salesman’s wool sample books. There ought to be something else, a small corked glass phial with the inscription: ‘Original Mauveine prepared by Sir William Perkin in 1856’. But a sign says it is in Osaka, and should be back by March. When it returns it will probably go into the big new gallery on the history of technology on the ground floor.
‘Dyes drove so many industries that it’s easy to forget that they totally changed the way the world looked,’ Dr Bud said. ‘Before the synthetic dyes, you could argue that rich patterns of exotic colours were an elite thing. After them, everyone lived with such colours as mauve.’
The display was designed to mark the sixtieth anniversary of the establishment of ICI. ‘We were going to paint the floor here white,’ Bud remembered, ‘to denote the fact that you were entering a new and important section. Unfortunately there was a strike and we couldn’t get it the way we wanted.’
Dr Bud considered why dyes were so important. ‘The textile industry was the big industry, so the moment you’ve got an artificial dye, you’ve got something that you can plug into the biggest industry. The other thing is the impact that this all has on people’s vision of what industrial chemistry is going to be. Even towards the end of the nineteenth century it is still a shock technology. Together with electricity, synthetic dyes made people think, “What’s next?” Drugs followed, then synthetic fibres and plastics, and they are all based on the vision and success of the synthetic colours. Perkin’s impact could be quantified in inspirational terms – in what science was now going to do to the world. Perkin’s world is one of enormous uncertainty about what the future holds: all you know is that the future is going to be different from the past.
‘The really big vision of how chemistry could be applied to industry had come earlier with Davy and Faraday developing new materials and later with Liebig’s fertilisers. But dyestuffs were an example of how you apply an entire discipline. It enabled chemists to a
nswer the question “What do you do?” with a practical demonstration.’
Dr Bud returned to his office with the thought that if he were to build the display again he might concentrate more on the romantic side of the Perkin story, ‘not just on dyes as a product. But in 1986 we weren’t living in a postmodern world.’
9
POISONING THE CLIENTELE
In a continuing effort at precision reporting, a New York Times reporter covering the O. J. Simpson trial found himself at a loss in describing the colour of defence lawyer Johnnie Cochran’s double-breasted suit. He dispatched a research assistant to a local drugstore to purchase a box of Crayola crayons, from which he selected the closest possible colour: periwinkle. In an informal poll, courthouse wags opted for the less precise purple. During a courtroom break, though, Cochran insisted his suit was blue. ‘Just don’t call it mauve,’ he said.
USA Today, February 1995
In 1870, a German chemist named Dr Springmuhl gathered fourteen samples of commercial magenta dye from his friends in Europe and checked them for traces of arsenic. Some of his findings were alarming. He found that nine of the samples consisted of at least 2 per cent arsenic, and five of them contained between 4.3 and 6.5 per cent. The colour was poisoning its purchasers.
His analysis was sponsored by the German government, some members of which had become concerned by newspaper reports that aniline dyes had caused inflammations on women’s skin. Under much pressure from its dye companies, the nation’s fastest-growing industry, the German government declared that women had nothing to fear. Dr Springmuhl’s work further examined the effect of his dyes on a square foot of wool, and found that while the dye-bath still contained high levels of arsenic poison, only a tiny fraction – 0.0001 of a gram – transferred to the surface of the dyed fabric.
Mauve Page 10
