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Letters : Think again

Chichester, West Sussex

While it is possible to learn to control a prosthesis from the
bioelectric potentials detected on the scalp, it is journalistic sensationalism
to imply that these potentials may reflect specific thoughts (“Thought Control”,
9 March, p 39).

Recent neuroscience indicates that thoughts, percepts, and so on are manifest
in neuron arrays involving many distributed microcolumns, each representing some
particular feature of the whole. Brain potentials at the scalp surface are so
blurred by the intervening tissues that they cannot reflect the subtleties of
content and of temporal variability of thought represented on this micro scale.
Even with surface arrays of 100 or more electrodes, they can only represent
gross neuron correlates of behaviour such as decisions relating to simple
sensorimotor events, or levels of attention or emotion.

Moreover, the electrical activity of scalp muscles and oculomotor activity
are several orders larger than scalp recorded brain potentials and are likely to
swamp any attempt to harness brain potential correlates of thought. They can
themselves more easily be used to control a prosthesis.

One might learn to control a prosthesis to make a particular chess move, but
scalp detected brain potentials will never indicate which gambit is intended. It
would be a pity if this interesting subject were to be tainted by the naive
enthusiasm that marred the developments in AI, as recently discussed in your
columns.

Letters : Pee on the roads

Edmonton, Canada

Tam Dalyell mentioned the use of urea as a de-icing agent for highways
(Forum, 17 February, p 46). He referred to it as having an “environmental
disadvantage: it oxidises when dissolved in water, giving off ammonia”. The
reaction involved is not oxidation but hydrolysis, and is induced by the
omnipresent enzyme urease.

The ammonia so released can be absorbed by nearby water bodies, and thus
stimulate aquatic life. It is also readily oxidised to nitrate by
chemautotrophic soil bacteria and can also enter water bodies in this form. Urea
itself is very soluble and can serve as a nitrogen source for many organisms
without either the hydrolysis or oxidation reactions.

Incidentally, sodium chloride is not without environmental hazards. In high
concentrations, as can occur along highways, it can harm organisms by lowering
the soil water potential (increasing the osmotic pressure).

Letters : What's the smell?

Sherborne, Dorset

There is no scientific basis for Clive Mather’s suggestion that air
pollutants can be “concentrated” near high-tension cables (Letters, 16 March, p
57). As regards direct chemical effects, silent discharges in air generate ozone
but noisy ones oxides of nitrogen.

Domestic air ionisers apply high-voltage DC to a sharp point and the air
blowing off that smells to me more of nitrogen dioxide than of ozone. At high
dilution, the latter has a perfume-like smell, while that of nitrogen dioxide is
“fresh” and reminiscent of celery. I wonder if Jonathan Hobley (ibid) is sure it
was ozone he smelt near a substation? According to the official figures,
nitrogen dioxide is thirty times less toxic than ozone.

Letters : Dissenting voice

Richmond, British Columbia, Canada

In regard to the “Internet phone”, I think that the technology should
have remained what it was two years ago—a “proof of principle” by a few
Unix programmers (“Nattering on the Net”, 2 March, p 38). Point-to-point voice
is best handled by regular phone lines, and point-to-point video is best handled
by ISDN lines.

The available bandwidth is better used for services like the multicast MBONE,
narrowcasting events such as scientific conferences to a global audience too
large for multipoint conferencing and too small for direct satellite TV (and of
course moving data and surfing Planet Science). Unless, of course, all telephone
trunks become part of the Internet as the phone companies cave in.

Letters : Nuclear post

Munich

Although Dan Charles talked personally to Manfred von Ardenne and quoted
his autobiography (Forum, 16 March, p 53), I cannot understand why he had to
emphasise that “During the Second World War, Ardenne was familiar with German
work on the nuclear bomb, but never joined the project”, when it is well known
that he was involved in nuclear research, even though financed by the Ministry
of Posts.

For instance, Richard Rhodes wrote in 1986 in his book The Making of the
Atomic Bomb: “When Hitler made his temporary pact with Stalin in 1939 it
included an exchange of prisoners, and Houtermans was handed back to the
Gestapo. Max von Laue managed to free Houtermans and arranged for him to work
with a wealthy German inventor, Baron Manfred von Ardenne, who studied physics
and who maintained a private laboratory in Lichterfelde, outside Berlin. Von
Ardenne was pursuing uranium research independently of Heisenberg and the War
Office; to raise funds for the work he had approached the German Post Ministry,
which commanded a large and largely unused budget for research.

“The Minister of Posts, imagining himself handing Hitler the decisive secret
weapon of the war, had funded the building of a million-volt Van de Graaff and
two cyclotrons, all under construction in 1941. Until they came online,
Houtermans turned his attention to theory. By August he had independently worked
out all the basic ideas necessary to a bomb . . . He discussed his ideas
privately with von Weizsäcker and Heisenberg, but he saw to it that the
Post Office kept his report in its safe, secure from the War Office eyes . . .”

Letters : Ban all beef

Bridlington East Yorkshire

Surely the Germans are right to ban all British beef on the grounds that
the argument for the confinement of the BSE agent to the central nervous system
is inconsistent?

Removal of the brain and spinal cord implies that this agent is confined to
the cerebrospinal fluid. Yet the disease is manifested in the mass of glial
cells and neurons. The projections of the latter extend from the spinal cord as
peripheral nerves into all tissues, especially the muscles.

Until the causation of this disease is revealed and in the absence of
statistically valid data, the only certainty is uncertainty at this stage.

• • •

It is now widely recognised that the disease of sheep scrapie jumped
species to cattle under the new name of BSE when cows were fed sheep remains. It
is increasingly feared that BSE can jump again to cause a strain of
Creutzfeldt-Jakob disease in humans.

Why, amid the rising panic about eating beef, have I heard no worries
expressed about eating lamb? Is there a scientific reason why scrapie cannot
jump direct to humans, or has nobody put two and two together?

T. J. Stevenson

Bracknell, Berkshire

No studies have as yet shown any correlation between the incidence of scrapie
in sheep and the incidence of CJD in humans—Ed

Letters : Collectors' item

Warrington, Cheshire

The report on attempts to rationalise legislation on fossil collecting in
the US highlights problems faced by fossil (and mineral) collectors in many
countries (This Week, 16 March, p 10). Opponents of collecting, usually either
ivory-towered academics or officious government or other bodies, seem oblivious
to the loss being caused all the time to our geological heritage by quarrying,
mining or construction work or by natural erosion. “Leave alone” policies may
work well for rare orchids or peregrine falcons but can be wholly inappropriate
for geological material. Fossils and minerals soon disintegrate once exposed and
there are just too few professionals with too little time (and funding) to
rescue them before they are destroyed.

Amateurs are continually making, and reporting, discoveries that would
otherwise have been missed or lost for all time. Many museum curators know the
benefits of having an army of often knowledgeable collectors and maintain good
relations with them—to everyone’s benefit. This applies equally well to
commercial collectors, many of whose finds grace our museums and whose
activities attract newcomers to the earth sciences. How many palaeontologists,
mineralogists and geologists first had their interest aroused as children thanks
to a trilobite or crystal purchased for a few pounds?

The enemies of collecting are strong, however. In Britain sections of Cornish
coastline are coming under the control of the National Trust, which will not
allow hammers. Sites are needlessly being labelled SSSIs so that whatever
material they may contain is now being left to the weather rather than being
taken safely indoors. Old mines are being sealed and their waste tips cleared,
access to quarries banned and so on. Before long the anti-collecting brigade
will have won—thanks to them there will be nothing left to collect.

Letters : Rhetoric and reason

London

The rhetoric of Ian Taylor, minister for science and technology, with
blanket assertions of “excellent budget settlement” and “favourable reactions”,
is just what you would expect from a representative of a government that has
been responsible for the decimation of independent research in science and
technology in Britain (Letters, 17 February, p 48).

We have seen the closure of many government scientific departments and
research organisations, their privatisation or just the lumping of them together
with considerable loss of scientific employment and cuts in funding. This has
been acknowledged in these columns for many years. For a government that has
been so economical with everything, why should the truth be any
different?

We have also seen the general destruction of a large amount of basic British
industry (particularly engineering) over the past 16 years, with foreign-based
transnationals taking its place. They have taken advantage of the weakness in
our industry, with its now subdued and compliant workforce ready to work for
lower wages. This has been very costly for Britain as a trading nation and has
spoilt our economic future compared with other countries.

Short-termism rules and the future is left to care for itself as best it can.
How many young and not-so-young scientists and technologists know where their
jobs will be next year, or if they will have a job at all? There is no
continuity, no money, no context in which to plan the future for many people
today.

Taylor’s letter is an elegant cover-up for years of cutbacks and
penny-pinching. Yes, the government would like to “harness the intellectual
resources” of talented people to “improve economic performance”, but who would
receive the improved “quality of life”?

It was reported recently that the British government is facing a deepening
crisis in the quality of higher education. With the contradiction of expanding
enrolment and funding cuts, the funding per student has fallen by one third
since 1989. According to Science (23 February, vol 271, p 1045),
“Deteriorating staff salaries and conditions have paid for the expansion, and
quality is suffering” and “Funding cuts have hit science departments directly,
with money for new equipment and buildings slashed by 30 per cent in November”.
This is the nation’s future in jeopardy!

The education and employment secretary, Gillian Shephard, has set up an
independent review under Ron Dearing. But this is unlikely to surface before the
next election. Will this review recommend the scrapping of free tuition for most
students?

Letters : Bowled out

Lewes, East Sussex

Has anyone else noticed how English cricket has become a metaphor for
British science? In cricket, we take gifted amateurs, pay them a pittance,
provide them with minimal training facilities, give them almost no moral support
and then expect them to take on the world.

Parallels with the treatment of science and scientists in British
universities are remarkable and, in both cases, I fear the end result will be
the same—relegation to the second division.

Letters : Oh no

Norwich

Charles Pochin points out the anomalous use of the letter O for the
number 0 in British telephone numbers (Letters, 2 March, p 50). Other European
countries cope with this rather better. For instance in Denmark the numbers
(eight digits) are always quoted in four blocks (so 3186-7050 would be said as
thirty-one, eighty-six, seventy, fifty). Any 00 combination is “null, null”
(zero, zero). With eight digits, this convention is simple.

In Britain, the length of numbers is variable and the many changes to STD
codes have made it harder for consistent usage to emerge. The use of 0 is well
established in spoken English (such as saying the number 306 as three oh six,
rather than three hundred and six). For a combination of reasons, we have
resisted breaking our numbers into two-digit combinations and therefore find
them harder to transmit accurately. Numbers tend to be given as single digits,
which can be confusing. My office number 222732, is tricky to convey using
phrases such as “two, double two”, or “triple two”, but simplicity itself when
expressed as “twenty-two, twenty-seven, thirty-two”.

Whether our usages will converge with the rest of Europe is a moot point.

Letters : Legless in space

Preston, Lancashire

“And whereas 45 per cent of American astronauts cannot fit in Soyuz, all
but the tallest 5 per cent of the population will fit inside the X-CRV…”
(“Lost in Space”, 16 March, p 40). But why should astronauts be large?
Larger-than-average people not only take up more space, they consume more air,
food, water and energy, and need more fuel to lift them off the Earth. It would
therefore make sense for space agencies to choose smaller-than-average people
for their programmes.

Going further, why should astronauts be physically perfect specimens? Legs
make up a large percentage of body mass and are mostly useless encumbrances in
space. The ideal astronaut would probably therefore be legless as well as
small.

Letters : Remember Mpemba

Hyde, Cheshire

With reference to Charles Knight’s observations about the Mpemba effect
(Letters, 16 March, p 58), I wonder if Mpemba knows that his name has entered
the language and that scientists are still debating the question that he put to
Professor D.G. Osborne at Iringa School, Southern Tanzania almost 30 years
ago.

When I showed Knight’s letter to my wife she reminded me that she had typed
Professor Osborne’s original article “Mpemba’s Ice-cream” in Dar es Salaam those
many years ago.

• • •

Knight recommends N. E. Dorsey’s study “The Freezing of Supercooled
Water”. Readers should be warned that this extends to 80 pages.

0ut of modesty, perhaps, Knight did not mention his own book The Freezing
of Supercooled Liquids (1967). This I found excellent.

J. Jocelyn

Scottish Universities Research and Reactor Centre

East Kilbride

Letters : Whingeing Brits

A recent conference at Leicester University concerned with the
restoration of lakes and reservoirs was attended by some 300 delegates from
seven countries. Only a few (possibly 20) academics from British universities
were present. Those that were there were dubbed the whingeing
professors.

This is hardly surprising. The cost of the conference was about £500,
far in excess of the total annual allowance available for many university staff.
In our case, the costs were met by consultancy earnings, our individual travel
budget being limited to £200. Most of those present came from the private
sector or agencies.

I suspect that 60 per cent of academics’ time is now spent scratching around
like headless chickens for limited research funds. Meanwhile, the equipment base
continues to decline with cuts in capital budgets. Those contributions from
established researchers were notable for their excellence and sheer
determination to succeed in the face of cuts.

The mismatch between the resources of institutions traditionally concerned
with training students and their target employers, which was very evident at the
conference, is not only a national disgrace but also an embarrassment to those
staff concerned.