Mauve. Simon Garfield
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incidentally, died twelve years before Perkin’s discovery, but the beauty would have been lost on him anyway: in 1794 he had been the first person to describe colour blindness – his own.
The principal reason that August Hofmann would have failed to share Perkin’s enthusiasm for his new colour was because he would not have been unduly surprised by it. Even before he came to London he had heard Liebig predict that artificial dyes would someday be made from a substance such as aniline. But the roots of his disapproval lay in the current relationship between pure and applied science, which really meant the relationship between science and industry, two worlds set against each other by deficiencies in education.
In 1853, Lord Lyon Playfair had travelled through Germany and France at the request of the Prince Consort, specifically to report back on the state of foreign scientific and technical education. His analysis was damning: the great universities of Europe had already forged a strong connection between laboratory work and industry, whereas in industrial Britain he found only an ‘overweening respect for practice and contempt for science’. He found the greatest culprit to be the severe shortcomings in basic teaching. Playfair feared the impact on Britain in the event of free trade, suggesting that when ‘the raw materials confined to one country become readily available to all at a slight difference in cost, then the competition in industry must become a competition in intellect’.
The Great Exhibition of 1851 inspired many lectures sponsored by the Society of Arts, and some of them singled out a peculiar irony: while Britain shook the world with its industrial clout, it was virtually alone in Europe in lacking a well-defined system of technical education.
The same year saw the opening of Owens College in Manchester, and at its inaugural gala the college’s professor of chemistry Edward Frankland suggested that Britain’s textile industry was ill-prepared for the future. Its pre-eminence in manufacture would only be maintained by far stronger links with men of science. ‘The advantages of chemistry to the chemical manufacturer, the dyer and calico printer are almost too obvious to require comment,’ he said. ‘These processes cannot be carried out without some knowledge of our science, yet with the exception of some few firms . . . this knowledge is too often only superficial, sufficient to prevent egregious blunders and ruinous losses, but inadequate to seize upon and turn to advantage the numerous hints which are almost sure to be constantly furnished in all manufacturing processes.’
The Chemical Society, founded in 1841, drew its few hundred members from manufacturing and academic backgrounds, and prided itself on the links between the two. In 1853, the president of the society, Frank Daubeny, seemed to express relief when he informed his members that Professor Robert Bunsen’s work on volcanic eruptions could be used as ‘undeniable evidence of the extensive utility of our pursuits’. Four years later, the new president W. A. Miller spoke of the invention of mauve as further proof of the burgeoning usefulness of their skills. ‘One of our Fellows, Mr Perkin, has afforded me the opportunity of bringing before you the results of a successful application of abstract science to an immediate practical purpose.’ At the time, he could hardly have known of the immense implications of this observation.
In fact, the successful application was still some months away, but when it came it did little to placate those who believed that Perkin’s intellect could be better employed elsewhere. Even in 1862, it appeared that Hofmann accepted Perkin’s breakthrough only very grudgingly. After visiting the International Exhibition that year in London, he still wished that ‘the care and time involved in an undertaking of such magnitude may not divert [Perkin] from the path of scientific enquiry, for which he has proved himself eminently qualified’. Such a pure attitude ran counter to the dominant industrial ambition of the age: the pursuit of wealth.
In retrospect, it appears that Perkin shared some doubts about his commercial ambitions, though not for fear of being thought greedy. He resolved to regard his foray into industry as a means to an end. Writing to his friend Heinrich Caro, he stated that at the time of his discovery, ‘for a scientific man to be connected with manufacturing was looked upon as infra dig.’ Scientists who crossed the line were treated as pariahs, betrayers of their calling. Perkin was worried that, should he fail, there would be no way back. ‘Even poor Mansfield, as soon as he started to be a manufacturer, sold his scientific instruments (I have his balance which I purchased from him) evidently with the idea that his research days were over,’ Perkin wrote. ‘This public opinion and example made me dread becoming a manufacturer, because research was the principal ambition of my life, and I determined so far as in me lay that I would not give this up, whatever I did.’
At the time, however, he kept this desire very much to himself, and was treated by some with disdain. ‘It was said that by my example I had done harm to science and diverted the minds of young men from pure to applied science, and it is possible that for a short time some were attracted to the study of chemistry from other than truly scientific motives.’ In other words, Perkin’s discovery affected the whole nature of scientific investigation: for the first time, people realised that the study of chemistry could make them rich.
How to Make Mauve: a modern method
Caution: Petroleum ether is extremely flammable. All evaporations should be performed under hoods (fume cupboards). No naked flames in the lab, please. Disposal of all chemical wastes should follow the standard procedures.
You will need:
2.3ml of water in a 5ml conical flask, to which add
52μl of aniline
6oμl of o-toluidine
I22mg of p-toluidine
600μl of 2N sulphuric acid
Stir, using a large spin vane, until the reactants have dissolved, heating gently if necessary. After solution, add 30mg of potassium dichromate in 160μl of water.
Stir for two hours. Very soon after the addition of K2Cr2O7, the solution will turn a vibrant purple. At the end of the reaction time, use a Pasteur filter pipette to draw off the liquid portion, which can be discarded.
Transfer the solid to a ceramic filter with a seated filter paper already in place. Using gentle suction filtration, wash the dark solid with distilled water until the washing is clear. Dry the remaining solid in an oven at 110°c for 30 minutes. Then wash the solid with petroleum ether until the washings are clear. Dry again for 10 minutes at 110°c.
Wash the remaining solid with a 25 per cent methanol/water solution until the liquid runs clear, being very careful not to contaminate the product. Evaporate this aqueous/alcoholic solution, transferring to a 5ml conical flask as soon as the total volume allows. After evaporation is complete, add 300μl of 100 per cent methanol to the remaining solid, shake to dissolve any soluble materials, and use a filter pipette to transfer the liquid to a clean 3ml flask. Carefully evaporate the liquid in a conical flask until it has a volume of 30μl or less. As the solution volume gets smaller, the purple colour should grow more intense. This final methanol solution contains the ultimate product – a 2mg yield of mauve.
This isn’t much mauve. To get more, you might like to ask all your friends or an eager class of chemistry students to conduct the same experiment, and then pool all the methanol solutions, before evaporating this en masse. A small piece of cotton cloth can then be dipped in the solution, then rinsed in water and dried. It makes a nice pocket handkerchief; the solution will colour three slim bow ties.
How to make a Nesselrode: a traditional method
The Nesselrode pudding, a frozen tower of chestnut, fruit, custard and cream, is the creation of Monsieur Mouy, chef to Count Karl Vasilyevich Nesselrode, the nineteenth-century Russian statesman best known for his role in the creation of the Holy Alliance. The pudding appears, to some acclaim, in one of the lengthy dinner parties in Proust’s A la recherche du temps perdu, but these days is seldom made, largely due to health considerations.
The Nesselrode has been described as ‘a two-day event, not counting the evening with the orange peel’. One day takes place in the freezer.
You will need (for six people):
½ cup chestnut purée