Grayson Kennedy's Blog

It is well translated and (mostly)

graysonkennedy — Sun, 18 Jul 2010 00:03:07 +0000

It is well translated and (mostly) well written.
Kemp is only occasionally boring (for example, on Ruskin’s economics, or ” breaking the first rule of boredom ” on his dreams), and Ruskin never is.
You can’t like him, but you must worship, despise and pity him; he is by turns sublime and ridiculous, a giant and a wimp.
Ruskin started writing when he was seven and didn’t stop until he was 70; in between he wrote more than almost anyone else in the 19th century, which was not a time of literary reticence. Kemp manages to give all this a satisfying shape.
Ruskin argued that art must not exist for itself, but for its subject, nature “”All Great Art is Praise”" and to express and enhance society and so that a worthless society could produce only worthless art, and vice versa.
And he argued, with endless gloomy relish and that England after the Industrial Revolution was becoming increasingly worthless. The life, of course, was hardly less extraordinary.
Kemp is brief but sensible about the mariage blanc to Effie; he is full, and dismaying, about Ruskin’s infantilism, manic depression, and Humbert Humbert obsession with a series of young girls. It seems that what drove him mad with guilt was masturbation. Perhaps some things have improved after all.
There’s little room left for my last choice,Juniper Hall by Linda Kelly.
This is a startling piece of historical research and imagination, about the flight to England of a group of French aristocrats in 179293.
One was the remarkable Madame de StaÃ«l; another was Alexandre d’Arblay, who met and married Fanny Burney.
Linda Kelly has made herself so familiar with these redoubtable historical figures that she writes about them as though they were her next-door neighbours. That makes for great freshness and immediacy, but also, I felt, for banality.
Although the French Revolution was far worse than anything that our other subjects ” except Gotfryd ” had to suffer, we get little sense of pain from this book. I hate to say it, but pain may be necessary to art.
Carole Angier’s biography Jean Rhys is published by AndrÃ© Deutsch (£17.99) DISTINGUISHING marques
COUPES, CABRIOLETS, HATCHES AND SALOONS: FRANK PAGE REVIEWS THE LATEST OFFERINGS FROM THE GARAGE SHOWROOMS
Despite the downturn in Britain’s car market (300,000 fewer cars sold last year than in 1989), new and better-equipped models continue to drop off the production lines at an astonishing pace.
And of these it is the small-to-medium family cars that sell in the greatest numbers.
Notable in this bracket is the new series of Ford Escort hatchbacks and Orion saloons.
The Escort has been one of Britain’s top-sellers for many years and having tested various examples of the latest in the range I have to give a curate’s egg verdict.
The improvements are the amount of space inside (thanks to the extended wheelbase) and the more refined suspension.
The disappointments are the continued use of the old 1.4 and 1.6 litre CVH engines (coarse at high revs) and the fainthearted styling.

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Kuwait’s Ministry of Power and Water last week…

graysonkennedy — Sun, 27 Jun 2010 20:18:03 +0000

Kuwait’s Ministry of Power and Water last week estimated that water supplies would last for 12 days if the slick reached desalination inlets, or for a month if the population was rationed to 4 litres per person per day.
Other Gulf states have fitted booms across the inlets of desalination plants, and suction equipment will clean up slicks.
But precautions are hampered by the fact that no one now knows where the slick is.
“We have only observed a few patches this week,” Fakhro said, “most of it is still in the war zone”.
One theory is that the oil has sunk, and is drifting in globules a few metres below the surface of the water.
Although the spill is the largest single oil accident in the Gulf and the waters are no strangers to pollution.
According to one report, by the Earthscan organisation and routine ballast-dumping alone accounted for 400 000 tonnes of oil pollution a year by the end of the 1970s.
Ironically and the International Convention for the Prevention of Marine Pollution will ban this type of dumping in the Gulf from 2 (Sober.
But, as a spokesman for the UN’s International Maritime Organisation said “there’s nothing to stop a tanker’s skipper dumping oil and blaming it on the war”.
Despite the Gulfs long history of oil pollution, little research has been done on the long-term impact on marine life there.
One survey, carried out in 1977 by Dr Anthony Nelson-Smith of University College, Swansea, found that oil “…has reached nearly all parts of the coast and sometimes in considerable quantities.
This has undoubtedly caused temporary local damage and may well have contributed to the general decline of the shrimp fishery.”
Two British experts on oil pollution travelled to Bahrain this week to see how marine life is coping.
One of them, Dr Andrew Price of York University and said he would be looking at the impact of the spill on turtles and shrimps and dolphins. The Gulf has seen nothing on this scale before.”
But worse disasters could come.
The Iraqi air force last week announced it would attack with Exocet missiles any ship taking on Iranian crude oil.
The sinking of a laden supertanker would make the present slick look small indeed. Accelerator was an expensive failure
ONE OF the centrepieces of Britain’s post-war high-energy physics programme ” the electron accelerator at Daresbury in Cheshire ” is this week labelled an expensive Failure by a research team.
Ironically Sir Alec Merrison and the laboratory’s director when the project was approved in 1962, warned then, in an article in New Scientist . of the dangers of the multi-million pound accelerator becoming a white elephant.
In its critique of the project and known as Nina and the Science Policy Research Unit (SPRU) of the University of Sussex and says: I Only six papers a year were produced from research using the machine, whereas similar devices abroad were producing up to twice as many The scientific impact of the work was minimal.
Research papers from Daresbury have not been quoted by other physicists as important reference material. Other accelerators had far more citations
Physicists in America and Europe had a low opinion of Nina and Daresbury’s physicists themselves thought it was mediocre.
John Irvine, who wrote the SPRU report with Ben Martin and told New Scientist that the results raise questions about British policy towards high-energy physics in the past 20 years.
“They show that a major capital investment, amounting to £160 million in current prices, did not produce much physics and should have been closed long before it was in 1977.”

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“He always had this burning ambition to start…

graysonkennedy — Sun, 20 Jun 2010 14:52:45 +0000

“He always had this burning ambition to start his own business.” With him went Goodwin and then finance director at Cables Montague.
“It was a family company and I couldn’t see any future for me as far as equity was concerned,” Goodwin says. At Tiphook he has 1.3 million shares, worth about £5 million. In the first year and the pair picked up backing from Gresham Trust.
From 1981, Friends Provident also pumped money into the business, bankrolling its expansion until it was floated in 1985. There was plenty of expansion to bankroll.
By the time Tiphook arrived on the stock market, it already had impressive turnover and profits for a company only seven years off the starting blocks; the following year it made £2.4 million profit on sales of £25 million. Between 1986 and 1990, it exploded.
Last year and turnover was £174 million and profits £33 million, a compound profit growth rate of 82 per cent(making it Britain’s 93rd-best profit performer over the period).
Somewhere along the line Montague had learned a valuable lesson: that money can fall off the back of a lorry.
“The principle of our business is that an asset can be financed and paid for, including interest and capital, in the first half of its working life,” he says. “After that, cash basically falls off the thing.”
The doubling this year of sales and profits will be thanks to Montague’s increasingly astute deal-making.
He has acquired two UK trailer rental businesses: Central Trailer Rental in 1982 and Rentco International in 1988. However and the turning point came in 1989, with a phone call from New York. Peter Wood, a banker at J.P.
Morgan, had been hired by family-controlled Swedish shipping line Stena to find a partner for its bid to buy James Sherwood’s Sea Containers.
Stena’s chief executive, Dan Sten Olsson, had set his sights on Sea Containers’ empire ” which included Sealink ferries and a fleet of 200,000 containers.
Olsson wanted a partner to buy the boxes, “someone fairly aggressive”, Wood says.
Any search for someone aggressive in the container business ” apart from Sherwood ” was bound to lead to Tiphook. Montague jumped.
“It was the chance of a lifetime,” he says.
The mechanics of the deal looked simple enough.
Tiphook would buy Sea Containers’ fleet, equivalent in size to its own.
Since the new boxes could be locked quickly into its computer and management system, operating costs would rise only by about 20 per cent. The remaining turnover from them would be pure profit.
There was one snag: Sherwood didn’t want to know.
The bid had to be hostile, and Tiphook and since it needed a rights issue to pay for its part of the deal, had to become a joint-bidder.

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Regular air services, by aeroplane, did not start until…

graysonkennedy — Sun, 20 Jun 2010 04:23:02 +0000

Regular air services, by aeroplane, did not start until after the First World War. Airships also began the first regular transatlantic services.
In the 1930s the Graf Zeppelin and, from 1936 and the Hindenburg ran regularly to Rio de Janeiro and the United States.
These services came to an abrupt halt in May 1937 when the Hindenburg burst into flames at Lakehurst, New Jersey. Thirty-three died, as apparently did passenger airships.
Transatlantic crossings by airship had ended before aeroplane services had begun. But in the past few years a phoenix has risen from the flames of Lakehurst.
Airships Industries, a firm backed by the Commercial Union insurance company, is developing a new range of airships.
The prototype, Skyship 500 (New Scientist, 2 September, p 616) is well on the way to getting a full certificate of airworthiness, and was demonstrated at this year’s Farnborough airshow. The Skyship differs from the 1930s” airships in two major respects.
Its lifting gas is not hydrogen, which is extremely flammable, but helium, which is inert.
And the Skyship is a pressure airship, whereas the old airships had rigid bodies.
A Greek firm has bought three Skyships, which will be used for coastal patrol and leased to Olympic Airways for luxury tourist travel in the Greek Islands. The Hindenburg was luxurious, comparable with liners like the Queen Mary.
The Hindenburg had a library,(passengers could borrow books), a 60-metre promenade deck, a sick bay with its own doctor and a lounge complete with a grand piano.
It also had a smoking room, which was furnished with one electric light and pressurised to prevent hydrogen seeping in.
But if airships were the last word in luxury then the penultimate word belonged to the flying boat.
It was a flying boat that started the transatlantic aeroplane service in 1937, which the Americans kept running even during the war.
[In fact, Lufthansa had pioneered an airmail service to South America in 1934, by way of a depot ship in the South Atlantic. The flying boat left the African coast and landed by the depot ship.
It was then hoisted aboard and refuelled and serviced and finally catapulted back into the air again]. Flying boats made a lot of sense in the early days of civil aviation.
Runways were usually grass, while a flying boat needed only a reasonably calm stretch of water [preferably without driftwood, which tore terrible holes in the thin hulls of these planes].
From 1937 Imperial Airways and the forerunner of BOAC, used flying boats on all its African services.
Its main flying boat aerodrome (if that’s the right word) was on the Solent, near Hythe, but Imperial Airways also ran to a number of other places around Britain, including the Pool of London. Flying boats were larger than most aircraft of the time.
The Boeing 247 a conventional plane which literally landed, was introduced in 1934. It carried just 10 passengers and together with two pilots and a stewardess.

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The US government’s Nuclear Regulatory Commission and…

graysonkennedy — Wed, 09 Jun 2010 20:45:42 +0000

The US government’s Nuclear Regulatory Commission and the private Electric Power Research Institute will also pay into the pot, which totals $93.5 million, for tests and for eventual decommissioning ” far cheaper than Super SARA.
Don McPherson, Britain’s man on the project and said the shadow of Super-SARA was a “tremendous hindrance” to negotiations for a LOFT consortium. But, he added, “we could have been a factor in the, failure of Super-SARA.
In fact, British scientists and engineers stand to save money handsomely, given the comparative cost of joining the LOFT consortium and helping to build Super-SARA.
Participation in LOFT is a key to Britain’s budding romance with PWRs and said McPherson.
“The UK felt it very important to be a member of LOFT while the (Sizewell) inquiry was going on and so they could demonstrate their seriousness in picking up the questions on safety”.
One of Britain’s representatives, Dr Jesse Fellow of the UK Atomic Energy Authority, is trying to persuade the members to run tests that will help the case for the Sizewell PWR at the inquiry.
Because of LOFT’s small size, Fell says, previous tests in which coolant water is shut off from the core have overstated the effectiveness of emergency systems designed to keep temperatures down.
Fell wants to simulate loss-of-coolant accident and then use about two-thirds the usual emergency cooling water to mimic what could occur at Sizewell.
Fell would also like to allow temperatures to rise high enough in the reactor to test theories about how fuel cladding could “balloon” at high temperatures as high-pressure helium builds up inside fuel rods in an accident.
The danger here is that this ballooning could cut off the emergency cooling water altogether. These new trials won’t come in time to make a difference at Sizewell.
Fell told New Scientist , “but Sizewell’s case has got to be made without relying on LOFT”.
Nonetheless and the assurance that someone will continue to put safety assumptions to the test could assuage some concern over the Sizewell reactor.
LOFT’s former director, Larry Leach, is now in Britain keeping tabs on the Sizewell inquiry for the US government.
Leach says LOFT is a boon to Britain because it can answer new questions raised by Britain’s stricter philosophy on safety margins.
That philosophy requires tests that have not been done before in the US, and that may never have been done but for the consortium’s help. Save the Black Forest
WEST GERMANY wants its partners in Europe to speed up work on combating acid rain by stricter controls on air pollution.

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The pay off is that there is little sign of the…

graysonkennedy — Fri, 28 May 2010 00:19:45 +0000

The pay off is that there is little sign of the peakiness that can accompany sports engines.
It pulls hard, evenly and far less raucously than an Astra GSi, Escort RS2000 or Renault 19 16v.
It becomes harsh only if you rev beyond the 6500rpm red line, a result of the engine’s willingness to accelerate all the way. There’s no excuse for not using the gears and though.
The change is light and precise although, if you’re lazy and the 16-valver is flexible enough to pull from 1000rpm.
The steering, geared at 2.5 turns between locks and power assisted, is delightfully responsive and, even in the wet, didn’t suffer badly from torque steer and thanks also to the 195/55 Michelin XGTVs wrapped round 15ins alloys.
Like all ZXs and the passive rear steer suspension gives superbly neutral handling, allowing you to exploit bends confidently and safely.
The five-door ZX has a reputation for its class-beating ride and the 16v also rides well, despite its stiffer springing and damping and a thicker rear anti-roll bar.
From the 16v down and the three-door ZX is every bit as excellent an all-rounder as its five-door parent.
With the two new models and strong pricing, Christmas might just come early for Citroen. Main dials are clear
Versatile loading ability
New 155bhp two-litre (left) is smooth and refined
Supportive seats
Rear space not great
The Autocar Long Term Test
Caterham 7 HPC
Can a Seven possibly stand 12,000 hard miles in eight months? Andrew Frankel finds out
For Wonderful to drive and own, cheap to insure Against Numerous niggling faults, hood design, vulnerable body I AM NOT LOOKING FORWARD to tomorrow.
That’s when the Caterham goes, eight months after five of us struggled for a weekend to built it in a cramped studio behind the office.
We have covered more than 12,000 miles together, during which it has won prizes, howled around Switzerland and Italy, been thrashed at Millbrook, and on race tracks and carried me home to Notting Hill through traffic and rain.

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Doctors employing the “neutralization technique”(see p 287),

graysonkennedy — Thu, 27 May 2010 13:31:01 +0000

Doctors employing the “neutralization technique”(see p 287), often give ethyl alcohol in sublingual drops (under-the-tongue drops) as neutralization therapy for mild forms of chemical sensitivity.
Ethyl alcohol , also known as ethanol , is the alcohol we use as a social lubricant in wines, beers and spirits. But what is used in sub-lingual therapy is industrial alcohol. This is made by adding water to ethylene gas, which itself is obtained from oil.
The theory is that industrial alcohol can desensitize someone to all synthetic organic chemicals, because it is derived from oil. It will be clear from the facts given above that this is highly unlikely.
Which is not to say that ethyl alcohol drops do not work ” they could help a chemical-sensitive patient by stimulating the liver to produce more detoxification enzymes. The chemical environment
Exposure to synthetic chemicals comes in three main forms ” by mouth and through the nose and lungs, and through the skin.
The sort of synthetic chemicals that we eat and drink are described in Appendix VI, p 305.
Those that we commonly breathe include solvents (see Table 3), exhaust fumes, cigarette smoke and aerosol droplets.
In addition to these, many people are exposed to fumes at work ” from industrial processes, photocopier machines or dry cleaning solvents, for example.
Those living in industrial areas, or near rubbish incinerators, are exposed to other airborne chemicals from these sources. The third source listed above ” the skin ” is far less important.
The number of synthetic chemicals that get into our bodies through the skin is relatively small, but solvents such as white spirit can enter in this way, as can oils and solvents used in cosmetics.
Someone eating an average diet and drinking unfiltered tap water is likely to ingest at least a hundred different synthetic chemicals every day ” see pp 30510.
Exposure to airborne chemicals will vary more widely, depending on where people live, what work they do, how well-ventilated their homes are, and what sort of household products they use.
A smoker in the house will increase the variety and quantity of air pollutants considerably.
In all, we are probably exposed to at least two hundred different synthetic chemicals every day ” and some people will encounter many more. WHAT CAUSES CHEMICAL SENSITIVITY?
Why are some people apparently made ill by everyday synthetic chemicals?
There are two types of explanation on offer, which can be summed up as “allergic explanations” and “deficiency explanations”.
The first type of theory proposes that these people make an inappropriate immune response (allergic response) to certain synthetic chemicals, in the same way that a hay-fever sufferer reacts adversely to pollen (see Chapter Two).
The second type of explanation suggests that these people have some sort of defect that makes them less able to cope with environmental chemicals.

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In a lower key, Sally Hacker describes…

graysonkennedy — Mon, 24 May 2010 02:14:58 +0000

In a lower key, Sally Hacker describes her research on how engineering students see the world, with some thought provoking insights into the part played by mind/body dualisms in perpetuating the contempt for all things female which characterises their views.
Much research and debate is required before we have a feminist theory of technology; in the meanwhile and this book will serve a useful purpose if it places the problem on the agenda of women’s studies. A measure of intelligence
Handbook of human intelligence edited by Robert Sternberg Cambridge UP, pp 1031, £45, pbk £15 Hans Eysenck
THIS is a very long, very expensive and very highlevel book on human intelligence which will undoubtedly become, for many years to come, and as far as it goes, a standard book of reference, It has five parts, dealing respectively with the nature of intelligence and its measurement; cognition, personality and intelligence; society, culture, and intelligence; the phylogeny and ontogeny of intelligence; and a metatheory of intelligence.
The contributors are well chosen, none having a special axe to grind, and all being experts in their fields.
In view of all these positive things, is it true to say, as the blurb does and that “the Handbook of Human Intelligence will guide thinking about intelligence for the rest of the century”?
I doubt it myself, for the reason that introduced the words “as far as it goes” above: the book simply leaves out of account the most important recent developments which foretell a revolution in the measurement and understanding of intelligence.
These developments can be understood only in the context of the long continued debate between two sides concerning the nature of intelligence, one captained by Sir Francis Galton and the other by Alfred Binet.
For Galton intelligence was a unitary, global mental capacity; for Binet it was merely the average of a number of independent, disparate abilities.
For Galton it was a gentle predisposition; For Binet it was strongly influenced by socioeconomic, cultural and educational factors.
For Galton the best method of measurement was physiological, or by reaction time; for Binet it was in terms of problem solving, learning and remembering following instructions, and other activities strongly involving learning.
Almost from the beginning Binet’s approach won the day, and this book is a celebration of his approach; unfortunately it may also be its epitaph.
In recent years, it has become clear that very simple measures of reaction time (particularly choice reaction time) and variability in reaction time correlate very highly with ordinary IQ measures and to an extent that makes much of the theorising in this book inapplicable, Similarly, measures of inspection time have shown uncommonly high correlations with IQ, particularly in below average subjects.
In these tests and two lines of obviously different lengths are exhibited for a very short period of time, and the subject has to say whether the right or the left line was the longer.
The shortest exposure time at which the subject succeeds better than 97.5 per cent is taken as the inspection time, with short inspection times being indicative of high intelligence.
Despite these outstandingly interesting and important findings, which support Galton and throw an entirely new light on the whole topic of intelligence, none of the contributors mentions the work of S. Lehrl and others in Germany, which demonstrates very high correlations between IQ tests and simple speed of naming of numbers and letters; this too throws much doubt on the theories embraced in this book.
Worst of all and there is no reference to the work on physiological measures of intelligence, begun by J. P. Ertl in Canada a dozen years ago.
Ertl showed that evoked potentials on the EEG showed shorter latency and greater amplitude for high IQ subjects than for low IQ subjects, In recent years this approach has been broadened and improved by the Hendricksons, and we now have physiological measures on the EEG evoked potential which correlate as highly with typical IQ tests as one of these IQ tests correlates with another!
Yet neither Ertl’s work nor the approach using evoked potentials and other physiological measures is discussed.
It is difficult to understand how such selectivity can be justified, in view of the fact that these studies and their results are quite incompatible with the major theoretical thrust of the book, which is complexly cognitive in the best Binet tradition.
This is a great pity; the battle between these two paradigms and that of Galton and that of Binet, is a very real one, and to pretend that it does not exist, and that there is no evidence against the paradigm adopted here, is disingenuous.
The book also shows the extremely irritating parochialism of American textbooks in psychology and to wit an almost complete exclusion of papers and books not written in English.
I have already commented on the book’s failure to mention the work of Lehrl, from West Germany: equally missing is the outstanding work of Volkmar Weiss and the Mehlhorns in East Germany, of A. Firkowska and others in Poland, of N. G. Lipovecheja and his colleagues in the USSR, and many others.

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Coming to terms mentally and emotionally with such…

graysonkennedy — Thu, 13 May 2010 01:39:38 +0000

Coming to terms mentally and emotionally with such change in an elderly relative is as much part of coping with the situation as providing the practical care that they need. At the receiving end
Elderly parents also have to grapple with a change in role.
Those who are mentally alert may not find it easy or pleasant to take help from the very ones they have supported and cared for over the years. Many parents dread the thought of having to depend on their children.
It is extremely painful for them to add to their burdens at a time when they are most hard pressed at work or with their own families.
Busy carers may make good provision for the physical needs of the parent without considering how they must be feeling.
Older people who have lived full and interesting lives will feel the loss of stimulus once they are housebound.
One woman, who took up a new career in midlife, described how her mother, who had always had a great appetite for life, now seemed.to live through her.
She took such an avid interest in all that her daughter was doing that it became stressful. But such intense interest can work to the carer’s advantage too.
Another older woman, who had lived alone with her mother since her father died and recalled the satisfaction of coming home to someone with all the time in the world to listen to what she had to tell about her day in the office or an evening at choir practice.
Now that her mother has died and she sadly misses the interest and advice that was always forthcoming.
Many of us have valued the interest focussed on our needs and problems by a parent who was physically disabled but mentally alert and concerned.
Others overlook this opportunity to share their interests with parents and don’t even seem aware of their parents’ need for mental and emotional stimulus.
Someone described seeing a couple having tea in a restaurant with an elderly parent.
Husband and wife kept up their own conversation and turning to the elderly lady from time to time only to offer her another cup of tea or a cake.
They no doubt thought that they were fulfilling their filial duty by providing her with an outing and “treat”. What kind of care?
Sooner or later it may become impossible for an elderly person or couple to continue living in their own home without support. There are various pointers that help us to decide when that time has come. They include:
badly failing sight
frequent falls
loss of memory

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A homogeneous “supercooled liquid” is created whose…

graysonkennedy — Wed, 12 May 2010 13:57:50 +0000

A homogeneous “supercooled liquid” is created whose structure is the instantaneous atomic arrangement of the liquid the moment it “freezes”.
The proportions of soda, lime and silica govern both the speed with which the molten oxide stiffens as the temperature falls and the temperature at which the glass finally solidifies.
Glasses containing large amounts of silica melt at very high temperatures; silica fuses at 1713 o C. The addition of soda has the opposite effect.
At 13000°C the viscosity of silica drops by a factor of ten thousand million (10 10 ) for the addition of 25 per cent of soda. Soda silica glasses are not very manageable, however.
They have too low a melting point and are too unstable, but they can be “stiffened” by adding a moderate amount of lime to produce a modest increase in melting temperature.
The optimum composition for glass to be manufactured in bulk has the approximate formula (Na2O), CaO(SiO2)s. Other ingredients can be added or substituted for different applications.
Glass-makers can use boron oxide (B2O3) in conjunction with silica to make glasses that do not expand too much on heating, as in Pyrex oven ware.
Lead oxide (PbO) increases the optical refractive index, bending light more as it enters the glass; “flint” glass for optical elements and “crystal”glass for tableware take advantage of this.
The oxide zirconium (ZrO2) improves the resistance of glass to attack by strong alkalis.
To understand all the variety of glass chemistry it is important to be able to picture the arrangement of atoms.
Physicists know only too well from studying crystalline materials that an understanding of solid-state physics is borne out of a sure knowledge of atomic structure and this has come traditionally from X-ray crystallography.
In the past decade, however, we have also learnt that to understand the physics of a solid we seldom need to know the “complete structure”; in most cases the “local structure” is sufficient.
The local structure is governed by chemical forces, while on the other hand the long-range order reflects the way structural units on the local scale pack together to form a three-dimensional solid.
Theorists can now solve the problems of solid-state physics in terms of the local structure, whereas previously they could deal only with materials where the complete structure was periodic and crystalline symmetry allowed them to make colossal simplifications.
But all this does not help with amorphous (non-crystalline) materials such as oxide glasses.
Although glasses in general do have a definite local structure their overall structure is disordered. As a result they diffract X-rays diffusely.
That is to say, in place of the regular “Weidoscope” pattern of spots that the regular planes of atoms in a single crystal generate and the diffraction pattern of a glass consists of haloes of uniform intensity (Figure 1).
Accordingly, instead of the three-dimensional geometry of atoms that can be obtained from the diffraction pattern of a crystal, a glass yields only a one-dimensional radial distribution.
In a multi-component disordered solid like soda-lime-silica glass a single spherically averaged diffraction pattern is quite inadequate.
There is no way we can decipher properly the individual contributions that different pairs of atoms make to the total atomic distribution.
We cannot, for instance, distinguish clearly between Na-O and Si-0 pairs, or Na-O and Ca-O pairs.
What is worse is that in glass sodium and calcium are more weakly bonded to oxygen than is silicon.
This means that Si-O distances dominate the distribution of atoms obtained from diffuse X-ray diffraction.
But, as I have described, it is ingredients such as soda and lime that alter totally the properties of Mass and whose local atomic structure is therefore especially interesting. This is the point at which synchrotron radiation comes to the rescue.

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