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Faraday: The Life
Faraday: The Life
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Faraday: The Life

Over the next few days Davy made more experiments on the mysterious purple flakes. The visitors probably left him to it, but Faraday was present, as his notes, written out in the Journal under 1 December, make clear. There was much controversy in Paris over whether Davy should have been given a sample to work on alone – Thénard and Gay-Lussac were ‘extremely angry’ with Ampère for giving some to Davy, because Gay-Lussac was intending to publish an analysis of ‘Substance X’.6

Davy repeated some of the experiments he had earlier tried in the presence of his visitors: bangs, whooshes, smoke and great stinks issued from the hotel room as he tried combining ‘X’ with iron, zinc, tin, potassium, ammonia. It was all done in tiny quantities, but the results were prodigious: ‘When solution of ammonia is poured on to the new substance and left in contact with it for a short time,’ Faraday recorded, ‘a black powder is formed which when separated, dried and heated, detonates with great force.’7

In carrying out all these tests, Davy was rapidly eliminating possibilities for the flaky substance, and approaching a definition. He was racing, in the short time he could spare, to find a solution to the puzzle, and above all to find it before Gay-Lussac or any other Frenchman did. Despite Gay-Lussac’s anger over the freedom Davy had been given to work on ‘Substance X’, Davy had a great respect for his rival. He described him as ‘quick, lively, ingenious, and profound, with great activity of mind, and great facility of manipulation. I should place him at the head of the living chemists of France.’8

This was undoubtedly a private battle of wits. Nicolas Clément moved into the fray when he gave a paper at the Institut showing that the substance could be produced by passing sulphuric acid through seaweed ash. But Gay-Lussac was the true rival, not least because Davy had unfinished business with him: three years earlier Gay-Lussac had allegedly suppressed the French publication of a paper on alkalis by Davy.9 Perhaps to size up the opposition, Davy and Faraday went to hear Gay-Lussac lecture on vapour to his students at the national school of chemistry in the École Polytechnique. ‘My knowledge of French,’ Faraday wrote later, ‘is so little I could hardly make out the lecture, and without the experiments I should have been entirely at a loss.’

After the lecture they were shown the enormous voltaic battery at the École, comprising six hundred pairs of plates, each seven or eight inches square, which at its best could produce six hundred volts. With some grim chagrin, Faraday noted that the battery had been paid for by the French government, while Davy had had to appeal to the patriotism of the Royal Institution Managers to raise money to buy one for England. He did not ask the government – there was not a hope of government money for scientific equipment in England until Charles Babbage drummed money out of the Exchequer for his Difference Engine in 1823.

Ten days after first being introduced to ‘X’, Davy went to the Jardin des Plantes, where Michel Eugène Chevreul had a laboratory, and the two scientists discussed and worked on the flaky substance together. Faraday was with them, taking notes. By 11 December Davy had concluded that it was an element standing alone, and he coined the name ‘iodine’, from the Greek for ‘violet-like’. On that day he did some final, conclusive tests, trying to pass a current through the material using Chevreul’s voltaic pile. He confirmed that it was an element, individual and apart, an analogue of chlorine, and thought it might come to be used to manufacture pigments, and in gunpowder. That was a fine triumph over French science, although as Faraday put it, with a trace of still lingering caution, ‘as yet it must be considered as a simple body’.10

With characteristic speed, Davy wrote a paper on iodine, with Faraday’s help as secretary in transcribing his atrocious handwriting and crossings out, which he rushed to the Royal Society in London to be read to his peers.11

While Davy was concluding his tests on iodine, Faraday was already expecting to leave Paris – he had written to his mother on 9 December saying as much.12 Sir Humphry had received his medal from the Institut, he had met fellow scientists, and he had clinched the iodine question. Nevertheless they stayed on for another three weeks, perhaps so that Davy could discuss iodine further and discover economic natural sources for it, less inherently dangerous than saltpetre. The Monday after Davy had reached his conclusions on iodine, Faraday records that he had at last seen the museum at the Jardin des Plantes; if he was accompanying Davy that day it suggests that Davy’s obsession with finding a source for iodine might have led him to pick over the exhibits in the museum and to discuss them with Cuvier, the Professor of Anatomy at the Jardin des Plantes. It is quite within Davy’s impulsive nature that he should change plans at a moment’s notice, and keep his entourage in uncertainty over what was to happen next. Davy had had many conversations with Cuvier. He had found the Frenchman eloquent in conversation, with ‘a great variety of information on scientific as well as popular subjects … the most distinguished man of talents I have known; but I doubt if he is entitled to the appellation of a man of genius’.13

From Davy this was a great compliment. Davy too was loquacious, a formidable conversationalist, and, like Cuvier, he came by the end of his life to extend his thought and philosophy to the widest realms of human society and happiness. Davy, however, merely thought and wrote about social progress; Cuvier, as a politician and courtier as well as natural scientist most famous for his interpretations of fossil remains, actually tried to put it into practice. He became a minister after the restoration of the monarchy under Louis XVIII, and stood up to Charles X when he put an end to the freedom of the press in July 1830. Under King Louis-Philippe Cuvier became Minister of the Interior.

The day after Faraday had seen some fossils at the museum in the Jardin des Plantes, those ‘astonishing organic remains’ of mammoths and other mammals that Cuvier had discovered at Montmartre, he walked across the city up the hill to Montmartre to try to find where they had come from, and with luck perhaps to dig up some more. But try as he might, with hand signals, a smattering of French and perhaps some exasperated English, he could not make the plaster-burners in the quarry understand what it was he wanted to see. It could not have been easy to make an early-nineteenth-century French workman understand by hand signals what a fossil was. As a result, Faraday did not get to the cliff to poke about, but he did take a good look at the geology of the place and, remembering Davy’s teaching, noted that ‘The rock is limestone and selenite and is burned for plaster on the spot … This stone is very imperfectly crystallized and looks more like calcarious sandstone. It is nearly all soluble in acids.’14

If the day had been clear, he might have been rewarded by an incomparable view of Paris. There in the middle distance, then beyond woods and ramparts, lay the city – a small carpet of white, cream, grey, and threads of dark red. The towers of Nôtre Dame stood out crisply, then as now, beside the florid Tour St Jacques, and the roofs of the Louvre draw a line which divides Paris in two along the river. The Seine, low-lying and kept in its place by embankments, is and was then barely visible from Montmartre. Floating upon the city like tethered hot-air balloons are the gleaming domes of the Institut, Les Invalides and the Pantheon, the only building to break the skyline at Montparnasse. But Faraday noted nothing about the view; what instead caught his eye was the clunking telegraph mounted on a tower nearby, which passed its unending semaphore messages to Paris from Boulogne and Lille. By means of the telegraph, Napoleon’s officials could communicate with each other rapidly. According to Andrew Robertson, who also saw the telegraph at work, it took six minutes for a message to reach Lille from Paris, and for an answer to be received.15 Faraday describes the telegraph relay, and adds a little drawing for good measure. He points out that ‘They are very different to the English telegraphs, being more perfect and simple.’16

There, standing on a Paris hillside, was a young citizen of an enemy country, who had already aroused the curiosity of the plaster-burners, sketching the equipment that kept Napoleon’s intelligence flowing around the country. How extraordinary that he was not arrested as a spy.

Wandering in these last few days more widely about Paris, Faraday watched a man touting for custom at a ‘Try your Strength’ machine on the Pont des Arts. He also tumbled to the answer to a problem that had been pestering him for some time – what was the occupation of ‘certain men who carry on their backs something like a high tower finely ornamented and painted and surmounted in general with a flag or vane’, which had a flexible pipe attached to it? The answer was that ‘these men are marchands des everything that is fit to drink’,17 water- or lemonade-carriers.

Sir Humphry had not yet made it clear to the party when they were to leave Paris. It had been on and off for days, but there must have been some indication that departure was imminent because on 18 December Faraday went to the Prefecture of Police to get a passport for interior travel in France, and on Christmas Eve he was writing: ‘we expect shortly to leave this city, and we have no great reason to regret it. It may perhaps be owing partly to the season and partly to ignorance of the language that I have enjoyed the place so little. The weather has been very bad, very cold, much snow, rain &c have continually kept the streets in a foul plight.’18

But there was one final fine Parisian extravaganza before they departed: Napoleon and the Empress Marie-Louise were to visit the Senate in full state on 19 December. The weather was cold and wet, but Faraday stuck it out on the terrace of the Tuileries, and eventually the long procession of trumpeters, guards and officers of the court wound into sight. At the end of the procession Faraday caught a glimpse of Napoleon in an opulent carriage surmounted by fourteen footmen, ‘sitting in one corner of his carriage covered and almost hidden from sight by an immense robe of ermine, and his face overshadowed by a tremendous plume of feathers that descended from a velvet hat. The distance was too great to distinguish the features well, but he seemed of a dark countenance and somewhat corpulent’ The Emperor was received by his citizens in complete silence: ‘no acclamations were heard where I stood and no comments’.19

There were, however, joyful acclamations from some members of Sir Humphry Davy’s party in the morning of 29 December, for, as Faraday writes, ‘this morning we left Paris’.20

CHAPTER 6 A Point of Light

They were all elated. It was freezing cold, bad enough for Sir Humphry and Lady Davy sitting inside the carriage, but deadly for those outside in the air. They were heading for Nemours, forty miles south of Paris, to spend the night, but it was evening before they reached the Forest of Fontainebleau. There had been no heat in the sun all day, and by evening the trees were still covered in hoar frost. This moved Faraday to lilting, Coleridgean prose.

… we did not regret the severity of the weather, for I do not think I ever saw a more beautiful scene than that presented to us on the road. A thick mist which had fallen during the night and which had scarcely cleared away had by being frozen dressed every visible object in a garment of wonderful airiness & delicacy. Every small twig and every blade of herbage was encrusted by a splendid coat of hoar frost, the crystals of which in most cases extended above half an inch. This circumstance … produced an endless variety of shapes and forms. Openings in the foreground placed far-removed objects in view which in their airiness, and softened by distance, appeared as clouds fixed by the hands of an enchanter: then rocks, hills, valleys, streams and roads, then a milestone, a cottage or human beings came into the moving landscape and rendered it ever new and delightful.1

Sir Humphry was also moved to such pictorial levels of passionate exclamation as they galloped through the forest. The experience drew the romantic poet out of him, forty lines of passion. This is a sample:

The trees display no green, no forms of life;

And yet a magic foliage clothes them round,-

The purest crystals of pellucid ice,

All purple in the sunset …2

This poem captures an essential difference in outlook between Faraday and Davy. In worldly affairs Faraday was naïve, ignorant, and wilfully avoided considering political issues. His understanding of the very dangerous situation in France was practically non-existent. Blundering about a Parisian quarry, patently the uninformed Englishman, openly sketching Napoleon’s telegraph equipment, he was being careless in the extreme. He felt an unfortunate, but at the time perfectly commonplace, kind of juvenile superiority over the French and the Italians, and this emerges regularly in his account of the continental journey.

Davy, however, though feeling superior to most people around him, had political antennae. He saw the importance of racing to an understanding of what iodine was before Gay-Lussac got to it; knowledge was power. He saw, too, the importance of putting on a theatrical show of chemical effects for the French scientists, and making them nervous. And he saw the importance of not appearing impressed by the treasures in the Louvre. So, at the end of his versification, Davy gives the lines a twist, and turns them into poetry. He draws a picture of a golden eagle on the gorge at Fontainebleau:

… the bird of prey, –

Emblem of rapine and lawless power:

Such is the fitful change of human things:

An empire rises, like a cloud in heaven,

Red in the morning sun …

… soon its tints

Are darken’d, and it brings the thunder-storm, –

Lightning and hail, and desolation comes;

But in destroying it dissolves, and falls

Never to rise!

Davy could handle allegory; indeed his whole imaginative life was wreathed in it, his visionary writings were driven by it, and his later writings suggest that towards the end of his life he was taken over by it. Faraday, on the other hand, saw the natural world as part of the revealed truth, the real thing, and his life’s work came to be dedicated to understanding the purposes behind nature – God’s purposes, in his view – and to explaining them in their most direct terms to humanity.

Riding through the Forest of Fontainebleau as the winter’s day, and the year 1813, drew to their close, Davy and Faraday were separated by more than the roof of the carriage. Davy was inside, looking out of the window to the right or left. Faraday, however, sitting up with the driver and the luggage, could see from an aerial perspective the entire 360 degrees around him, and the zenith of the skies. The man of allegory was enclosed from the world; the budding scientist of revealed truth was out within the elements.

It took them five days to reach Lyons. Faraday writes of travelling hastily, faring meagrely and arriving ‘fatigued and at a late hour’ at one of their stops on the way.3 It was a difficult and uncomfortable trip, to say the least. But even after the ecstatic experiences of Fontainebleau there were more natural joys for them to witness. They set off before dawn, without knowing where they would sleep that night. ‘These dark hours however have their pleasures, and those are not slight which are furnished at such hours by the memory or the imagination,’ wrote Faraday. As the sun went down in the Burgundian hills they saw crepuscular rays, or ‘Zodiacal light’, as Faraday described it. ‘It appeared as an emanation of light in enormous rays from the sun into the expanse. There were about seven rays diverging upwards and sideways and ascending many degrees into the heavens. They continued for nearly half an hour …’.4

The horses splashed through the waters at the edge of the Loire as they galloped down to Lyons in the starlight. In the gorges of the Auvergne they walked ‘for some miles through these wild valleys and passes’, to rest the horses and for Sir Humphry to investigate the extinct volcanoes.5 This was one of the main purposes of this part of the journey – Napoleon himself wanted Davy to study volcanoes.6 ‘We seem tied to no spot, confined by no circumstances, at all hours, at all seasons and in all places,’ Faraday wrote, using words which have a distinct echo, remarkable in a young non-conformist, of a significant passage in the Anglican Holy Communion service.

We move with freedom. Our world appears extending and our existence enlarged. We seem to fly over the globe rather like satellites to it, than parts of it, and mentally take possession of every spot we go over … We have lived hard this last day of the year.7

But a few days into January 1814 they began to feel the welcome of the warm south. The weather gradually lost its icy grip, and their spirits rose at these first hints of a Mediterranean climate. Sir Humphry reached for his pencil:

The air is soft as in the month of June

In northern climes; a balmy zephyr blows,

And nothing speaks of winter’s harshest month

Save that the trees are leafless …8

Looking about the Rhône near Lyons, he saw the landscape with the eye of an eighteenth-century connoisseur:

… and all the tints

Which human art bestows upon the scene

Are chaste as if the master-hand of Claude

Had traced upon the canvass their design.

They first saw the Alps from outside Lyons. Mont Blanc ‘was readily distinguished’, Faraday writes, giving the facts as he saw them:

It appeared as an enormous isolated [?] mass of white rocks. At sunset as the light decreased, their summits took a hundred varying hues. The tone of colouring changed rapidly as the luminary sank down, became more grave, at last appeared of a dull red as if ignited, and then disappeared in the obscurity, until fancy and the moon again faintly made them visible.9

Sir Humphry, however, put his first view of Mont Blanc in his own poetic way:

With joy I view thee, bathed in purple light,

Whilst all around is dark; with joy I see

Thee rising from thy sea of pitchy clouds

Into the middle heaven …10

They were heading for Montpellier, where Davy knew there would be a good supply of seashore plants and sea creatures that might be rich sources of iodine. When they reached the town, eleven days after leaving Paris, Faraday climbed to the Place Peyrou, the highest point. From there he had ‘a clear unsullied view of the beautiful and extensive landscape. From this spot I could see around me the Alps, the Pyrenees, the Mediterranean and the town as well as the country in the near neighbourhood.’11

They remained a month in Montpellier. Sir Humphry disappeared into the hinterland and to the sea’s edge to look for sources of iodine, and presumably he took Faraday with him, though the Journal is not clear about this. They must have gone together on a four-mile walk to Mont Ferrier, an extinct volcano, which had blown a huge ball of basalt for two miles when it erupted in deep geological time, and this had become a small mountain in its own right. By now the volcano had become a settlement, and gave evidence to suggest that the earth had been formed through the heat of volcanic activity. Faraday and Davy were both attracted by the olive and pine trees: ‘the pines are short but airy’, Faraday noted. Davy, however, went much further, and the day after their visit to Mont Ferrier composed thirty-one lines of verse to ‘The Mediterranean Pine’:

Thy hues are green as is the vernal tint

As those fair meads where Isis flows along

Her silver floods …

From this poetic description Davy moves into the ancient past, describing places and events in world history on which the pine has cast its shade – the teaching of Socrates and Plato, Greek democracy, Roman virtue, the teachings of Christ and the wanderings of the Jews.

There is a powerful energy crossing the gap between Faraday’s approach to what he is seeing, and Davy’s. The natural distance between enthusiasm and experience, pupil and teacher is palpable. Writing as they do in such different ways about the same landscapes, the same views, the same daily experiences, even the same kind of tree, suggests that during the conversations that must have taken place on Faraday and Davy’s walks – even if they were broken by the effort of the walk, or stilted by the gap in status, age and social position – there was also a growing fault-line in attitude, laying down early markers of the distance and distaste that later grew between them. At the moment, however, the distance was small, and for Faraday, if not for Davy, the ideas that flew from one to the other were like electric sparks passing between two separated wires.

While Sir Humphry picked over the Mediterranean flora, Faraday made his own wanderings about Montpellier. The weather had taken a turn for the worse, but even so Faraday was very much happier in Montpellier than he had been in Paris: ‘The shops are pretty, and many well-furnished and kept. The markets seem busy places, the coffee houses well frequented. The inhabitants are respectable and I have found them very good natured and obliging. The weather alone is what we did not expect it to be.’12

He had time on his hands once again, and he writes of pacing the aqueduct at the Place Peyrou to discover its length, 792 of his paces.13 Here is another example of Faraday’s enthusiastic concern for facts, dimension, physical reality and record emerging yet again, as it did in the notes he took of Tatum’s and Davy’s lectures, and in his accounts of the continental journey so far. But as Faraday was rambling about pacing the antiquities and Sir Humphry was gathering plants, Montpellier was gearing up for war. There was a straggling resident army, a fort above the town, and some hot-headed inhabitants. Their enthusiasm to resist the oncoming armies of the Duke of Wellington was consuming and patriotic. Nevertheless, Michael Faraday, an innocent abroad, did not seem to sense the dangers. On the Esplanade he noticed the pillar surmounted by Napoleon’s eagle and the gilded letter N, but dismissed it as ‘ostensibly placed as an embellishment, but really intended to produce a political effect’.14 He even took the extraordinary risk of walking around the fort, which was full of soldiers, while the cannon were firing – ‘I do not know what for, nor could our host tell me.’

‘The stroll around the ramparts was pleasant,’ he writes disarmingly, ‘but I imagine that at times whilst enjoying myself I was transgressing, for the sentinels regarded me sharply, and more particularly at least I thought so as I stood looking at one corner, where from some cause or other the fortifications were injured.’15 But nobody challenged him, and he had a wonderful view. After his rash behaviour when confronted by Napoleon’s semaphores at Montmartre, it was just as well he did not take out his notebook and sketch at Montpellier.

Great world events were passing under Faraday’s very nose in that place, but he did not seem to fathom their importance. His entry for Tuesday, 1 February is restricted to: ‘This morning the town was all in uproar and running to see the passing of a large train of artillery which is going up towards Lyons. They seem in great haste.’16

And four days later, having amused himself by standing at the edge of the parade ground and watching the clumsy square-bashing:

Drilling is now the occupation of the town, and the Peyrou looks like a Parade. During the morning it is covered by clusters of clumsy recruits who are endeavouring to hold their arms right, turn their toes out, keep their hands in, hold their hands up &c according to the direction of certain corporals who are at present all authority and importance.17

Then, as if it were merely a passing show, ‘The Pope passed through this place a few days ago in [sic] his way to Italy. He has just been set at liberty … Almost every person in the town was there but myself.’18