Uncle Tungsten: Memories of a Chemical Boyhood (2001) (38 page)

25
David Knight, in his brilliant biography of Davy, speaks of the passionate parallelism, the almost mystical sense of affinity and rapport, that Coleridge and Davy felt, and how the two planned, at one point, to set up a chemical laboratory together. In his book
The Friend
, Coleridge wrote:

Water and flame, the diamond, the charcoal…are convoked and fraternized by the theory of the chemist…It is the sense of a principle of connection given by the mind, and sanctioned by the correspondency of nature…If in a
Shakespeare
we find nature idealized into poetry, through the creative power of a profound yet observant meditation, so through the meditative observation of a
Davy
…we find poetry, as it were, substantiated and realized in nature: yea, nature itself disclosed to us…as at once the poet and the poem!

Coleridge was not the only writer to ‘renew his stock of metaphors’ with images from chemistry. The chemical term
elective affinities
was given an erotic connotation by Goethe; Keats, trained in medicine, reveled in chemical metaphors. Eliot, in ‘Tradition and the Individual Talent,’ employs chemical metaphors, from beginning to end, culminating in a grand, Davyan metaphor for the poet’s mind: ‘The analogy is that of the catalyst…The mind of the poet is the shred of platinum.’

26
The great chemist Justus von Liebig wrote powerfully about this feeling in his autobiography:

[Chemistry] developed in me the faculty, which is peculiar to chemists more than to other natural philosophers, of thinking in terms of phenomena; it is not very easy to give a clear idea of phenomena to anyone who cannot recall in his imagination a mental picture of what he sees and hears, like the poet and artist, for example…There is in the chemist a form of thought by which all ideas become visible in the mind as the strains of an imagined piece of music…

The faculty of thinking in phenomena can only be cultivated if the mind is constantly trained, and this was effected in my case by my endeavouring to perform, so far as my means would allow me, all the experiments whose description I read in the books…I repeated such experiments…a countless number of times,…till I knew thoroughly every aspect of the phenomenon which presented itself…a memory of the sense, that is to say of the sight, a clear perception of the resemblance or differences of things or of phenomena, which afterwards stood me in good stead.

27
Davy went on with his investigations of flame, and, a year after the safety lamp, published
Some Philosophical Researches on Flame
. More than forty years later, Faraday would return to the subject, in his famous Royal Institution lectures on
The Chemical History of a Candle
.

28
Enlarging on Davy’s observation of catalysis, Dobereiner found in 1822 that platinum, if finely divided, would not only become white-hot, but would ignite a stream of hydrogen passing over it. On this basis he made a lamp consisting basically of a tightly sealed bottle containing a piece of zinc which could be lowered into sulphuric acid, generating hydrogen. When the stopcock of the bottle was opened, hydrogen gushed out into a small container holding a bit of platinum sponge, and instantly burst into flame (a slightly dangerous flame, because it was virtually invisible, and one had to be cautious to avoid being burned). Within five years, there were twenty thousand Dobereiner lamps in use in Germany and England, so Davy had the satisfaction of seeing catalysis at work, indispensable in thousands of homes.

29
1 was intrigued, too (though I never practiced it), by cine-photography. Here again it was Walter who made me realize that there was no actual movement in the film, only a succession of still images which the brain synthesized to give an impression of movement. He demonstrated this to me with his film projector, slowing it down to show me only the still images, and then speeding it up until the illusion of motion suddenly occurred. He had a zoetrope, with images painted on the inside of a wheel, and a thaumatrope, with drawings on a stack of cards, which when rotated, or rapidly flicked, would give the same illusion. So I had the sense that movement, too, was constructed by the brain, in a manner analogous to that of color and depth.

30
Wells’s reference to the Martians’ unknown element also intrigued me later when I learned about spectra, for he described it, early in the book, as ‘giving a group of four lines in the blue of the spectrum,’ though subsequently – did he reread what he had written? – as giving ‘a brilliant group of three lines in the green.’

31
Yet Proust’s view was challenged by Claude-Louis Berthollet. A senior chemist of great eminence, an ardent supporter of Lavoisier (and a collaborator with him on the Nomenclature), Berthollet had discovered chemical bleaching and accompanied Napoleon as a scientist on his 1798 expedition to Egypt. He had observed that various alloys and glasses manifestly had quite varied chemical compositions; therefore, he maintained, compounds could have a continuously variable composition. He also remarked, when roasting lead in his laboratory, a striking, continuous color change – did this not imply a continuous absorption of oxygen with an infinite number of stages? It was true, Proust argued, that heated lead took up oxygen continuously and changed color as it did so, but this was due, he thought, to the formation of three distinctly colored oxides: a yellow monoxide, then red lead, then a chocolate-colored dioxide – admixed like paints, in varying proportions, depending on the state of oxidation. The oxides themselves might be mixed together in any proportion, he felt, but each was itself of fixed composition.

Berthollet also wondered about such compounds as ferrous sulphide, which never contained exactly the same proportions of iron and sulphur. Proust was unable to give a clear answer here (and indeed the answer only became clear with a subsequent understanding of crystal lattices and their defects and substitutions – thus sulphur can substitute for iron in the iron sulphide lattice to a variable extent, so that its effective formula varies from Fe
₇
S
₈
to Fe
₈
S
₉
. Such nonstoichiometric compounds came to be called berthollides).

Thus both Proust and Berthollet were right in a way, but the vast majority of compounds were Proustian, with a fixed composition. (And it was perhaps necessary that Proust’s view became the favored one, for it was Proust’s law which was to inspire the profound insights of Dalton.)

32
Though Newton hinted, in his final
Quaerie
, at something that almost seems to prefigure a Daltonian concept:

God is able to create particles of matter of several sizes and figures, and in several proportions to the space they occupy, and perhaps of different densities and forces.

33
Dalton represented the atoms of elements as circles with internal designs, sometimes reminiscent of the symbols of alchemy, or the planets; while the compound atoms (which we would now call ‘molecules’) had increasingly intricate geometric configurations – the first premonition of a structural chemistry that was not to be developed for another fifty years.

Though Dalton spoke of his atomic ‘hypothesis,’ he was convinced that atoms really existed – hence his violent objection to the terminology Berzelius was to introduce, in which an element was denoted by one or two letters of its name rather than his own iconic symbol. Dalton’s passionate opposition to Berzelius’s symbolism (which he felt concealed the actuality of atoms) lasted to the end of his life, and indeed when he died in 1844 it was from a sudden apoplexy, following a violent argument defending the realness of his atoms.

34
These names for metallic trees came from the alchemical notion of the correspondence between the sun, the moon, and the five (known) planets with the seven metals of antiquity. Thus gold stood for the sun, silver for the moon (and the moon goddess, Diana), mercury for Mercury, copper for Venus, iron for Mars, tin for Jupiter Qove), and lead for Saturn.

35
A discovery that for some reason especially interested me was Faraday’s discovery of diamagnetism in 1845. He had been experimenting with a very powerful new electromagnet, placing various transparent substances between its poles to see whether polarized light could be affected by the magnet. It could, and Faraday now found that the very heavy lead glass that he had used for some experiments actually moved when the magnet was switched on, aligning itself at right angles to the magnetic field (this was the first time he used the term
field
). Prior to this all known magnetic substances – iron, nickel, magnetite, etc. – had aligned themselves along the magnetic field, rather than at right angles to it. Intrigued, Faraday went on to test the magnetic susceptibility of everything he could lay his hands on – not only metals and minerals, but glass, flames, meat, and fruit, too.

When I spoke of this to Uncle Abe, he allowed me to experiment with the very powerful electromagnet he had in his attic, and I was able to duplicate a lot of Faraday’s findings, and to find, as he had, that the diamagnetic effect was especially powerful with bismuth, which was strongly repelled by both poles of the magnet. It was fascinating to see how a thin shard of bismuth (as near a needle as I could get with the brittle metal) aligned itself, almost violently, perpendicular to the magnetic field. I wondered whether, if it was sufficiently delicately poised, one might make a bismuth compass that pointed east-west. I experimented with bits of meat and fish, and wondered about experimenting with living creatures, too. Faraday himself had written, ‘If a man could be in the magnetic field, like Mahomet’s coffin he would turn until across the magnetic field.’ I wondered about putting a small frog, or perhaps an insect, in the field of Uncle Abe’s magnet, but feared this might freeze the motion of its blood, or blow its nervous system, turn out to be a refined form of murder. (I need not have worried: frogs have now been suspended for minutes in magnetic fields, and are apparently none the worse for the experience. With the vast magnets now available, an entire regiment could be suspended.)

36
He was distracted, too, creatively, by a dozen competing interests and commitments during this time: the investigation of steels, the making of special highly refractive optical glasses, the liquefaction of gases (which he was the first to achieve), the discovery of benzene, his many chemical and other lectures at the Royal Institution, and the publication in 1827 of his
Chemical Manipulations
.

37
Having no higher mathematics myself, unlike Uncle Abe, I found much of Maxwell’s work inaccessible, whereas I could at least read Faraday and feel I was getting the essential ideas, despite the fact that he never used mathematical formulas. Maxwell, expressing his indebtedness to Faraday, spoke of how his ideas, though fundamental, could be expressed in nonmathematical form:

It was perhaps for the advantage of science that Faraday, though thoroughly conscious of the fundamental forms of space, was not a professed mathematician…and did not feel called upon…to force his results into a shape acceptable to the mathematical taste of the time…He was thus left at leisure to do his proper work, to coordinate his ideas with the facts, and to express them in natural untechnical language…[Yet, Maxwell continued] As I proceeded with the study of Faraday I perceived that his method of conceiving the phenomena was also a mathematical one, though not exhibited in the conventional form of mathematical symbols.

38
Sir Ronald Storrs, the British governor of Jerusalem at the time, described his first encounter with Annie in his 1937 memoir,
Orientations
:

When, early in 1918, a lady, unlike the stage Woman of Destiny in that she was neither tall, dark nor thin, was ushered, with an expression of equal good humour and resolution, into my office I immediately realized that a new planet had swum into my ken. Miss Annie Landau had been throughout the War exiled…from her beloved…girls’ school, and demanded to return to it immediately. To my miserable pleading that her school was in use as a military hospital she opposed a steely insistence: and very few minutes had elapsed before I had leased her the vast empty building known as the Abyssinian Palace. Miss Landau rapidly became very much more than the headmistress of the best Jewish girls’ school in Palestine. She was more British than the English…she was more Jewish than the Zionists – no answer from her telephone on the Sabbath, even by the servants. She had been friendly with the Turks and Arabs before the War; so that her generous hospitality was for many years almost the only neutral ground upon which British officials, ardent Zionists, Moslem Beys and Christian Effendis could meet on terms of mutual conviviality.

39
‘The compound forming the incense,’ the Talmud prescribed in almost stoichiometric terms,

…consisted of balm, onycha, galbanum and frankincense, in quantities weighing seventy manehs each; of myrrh, cassia, spikenard and saffron, each sixteen manehs by weight; of costus twelve, of aromatic bark three, and of cinnamon nine manehs; of lye obtained from a species of leek, nine kabs; of Cyprus wine three seahs and three kabs: though, if Cyprus wine was not procurable, old white wine might be used; of salt of Sodom the fourth part of a kab, and of the herb Maaleh Ashan a minute quantity. R. Nathan says, a minute quantity was also required of the odoriferous herb Cippath, that grew on the banks of the Jordan; if, however, one added honey to the mixture, he rendered the incense unfit for sacred use, while he who, in preparing it, omitted one of its necessary ingredients, was liable to the penalty of death.