Letters: Teaching trauma
Having recently completed a PGCE in secondary science, I come with some
bad tidings for those wishing to inspire tomorrow’s scientists by this route
(Careers, 4 September).
As many educationalists will tell you, the sheer pace of new initiatives
in education is leaving not only teachers disorganised but equally the bodies
which train them. The whole process is akin to doing surgery on someone
in a rocking chair.
Much of the ‘on the job’ training is offered by schools in very tight
financial situations – precisely those with the least resources (including
staff time) to help trainees.
Neil Harris mentions the budding joint teacher-training programmes being
run by schools and higher education establishments. Many such courses are
in an embryonic stage and as such have little experience of the effect of
their programmes on teacher quality. That is not to say that they are not
working to improve matters. It is just that whatever they do will not eradicate
a fundamental flaw in the evolving system – the lack of public investment
in the infrastructure of our schools.
At the start of my PGCE the prospect of becoming one of a dying breed
of polymaths appealed to me. The stark reality is that this dream will take
many more years to realise than I anticipated, not least because so much
pedagogical theory must now be gleaned ‘on the hoof’ from teachers, whose
ability to look objectively at education has to be questioned.
So, if you are thinking of a career in science teaching it may be advisable
to consider the longer term training options (such as a BEd) which will
give you more time to reflect on your teaching approaches and get a better
perspective of general science teaching.
As for me – I’ll be teaching in France until the storm has blown over.
A. Thompson Paris
Letters: Spook-free letters
‘The mystery is deep,’ says Jim Baggott of the Einstein-Podolsky-Rosen
paradox in quantum mechanics (Review, 11 September). Quantum entities made
in pairs each carry information about the other when they zip off in opposite
directions. Measure the state of one, and you know the state of the other
even if it is light-years away. ‘Spooky action at a distance,’ said Einstein
himself.
If I write a letter, xerox it, and post the two resulting pieces of
paper to two people hundreds of miles apart, then each of them will be reading
the same thing the next morning. Further, if they both know what I’ve done,
then each knows exactly what the other is reading. This is an entirely spook-free
process.
Do the Schrodinger’s-cat letters exist before the envelopes are opened?
An absorbing question, but not one that has anything to do with physics.
The question is one for epistemology – it’s about what we choose to mean
by the verb to exist when we apply it to information. Nobody thinks that
the question ‘Would mathematics exist if there were no minds to apprehend
it?’ is for physics to answer, interesting though it is.
People love mysteries; you only have to look at how they act when some
prankster tramples flat a bit of corn in a field to see that. But physics
has enough appeal on its own, without needing to manufacture mysteries by
importing meaning-games from epistemology. The EPR ‘paradox’ has a resolution
that is as quotidian as the writing of a letter.
Adrian Bowyer University of Bath
Letters: Rooting out errors
We were pleased to read ‘Soil bugs home in on roots’ (New 杏吧原创,
Science, 4 September) which summarises some of our work. However. the article
was written without consulting us and is incorrect in a number of important
(and somewhat embarrassing) aspects.
Firstly the work referred to was done Mike Morris and Brian Reid in
my laboratory at Aberdeen University, not Dundee University as published.
The organism we work on, Phytophthora palmivora is of course a fungus, not
a bacterium. We have not suggested that the electrical current of roots
draws charged nutrients to the root surface (we are not sure where this
idea came from but earlier work in my lab suggests that this is unlikely
as far as phosphate is concerned).
Finally in the penultimate paragraph the author incorrectly states that
the spores are ‘attracted to the very parts of the root that behave as a
negative electrode’ – in apparent contradiction to the tactic behaviour
we report in our Plant, Cell & Environment paper. In fact we have since
discovered the mechanism of sensing of the electrical field and shown that
anodotactic zoospores accumulate at anodic parts of the root while cathodotactic
zoospores are attracted to the cathodic sites (such as plant wounds).
Neil Gow University of Aberdeen
Letters: Crowd-free zone
I agree with David Shrewsbury (Letters, 4 September) that the thought
of 400 passengers ashore at some Antarctic landing sites is indeed a horrifying
prospect.
However, voluntary guidelines agreed by member companies of the International
Association of Antarctica Tour Operators (IAATO) recommend that no more
than 100 should be on shore at one time. As expedition leader aboard a 400-passenger
ship in Antarctica early this year, I can reassure him that we observed
this guideline. Our passengers were always accompanied by between five
and eight guides.
Nigel Sitwell London
Letters: Caption complaint
The caption entries in my First Encyclopedia of Science quoted by your
reviewer did not please me, either (Review, 4 September). But encyclopedia
publishers reuse libraries of stock illustrations, and employ staff writers
to caption them. They are contractually beyond the author’s responsibility.
Brian Ford Eastrea, Cambridgeshire
Letters: Doughnut dilemma
If Francis Slakey, an American adjunct professor of physics, has not
the wit to reason out the purpose of the hole in the doughnut (Forum, 11
September) then what chance have we humble artisans of a reasoned chance
of survival? Ignorance of the elementary, it seems, is often coupled with
elevation to high places.
I remember my mother explaining the function of the hole to me at about
the time I failed my 11+ examination; some 45 years ago. The doughnut is
apparently cooked quickly in very hot fat. The centre of the ball of dough
is removed to allow the heat to be transferred quickly to the core of
the now toroidal shape thus preventing a large, undercooked mass in the
centre.
No doubt there are effective formulae for the function, but this reasoned
explanation should convince Professor Slakey of the perfection of his proof
of his own thesis, ‘Ignorance, it seems, is our destiny’.
Jeff Wheeldon Seaton, Devon
Letters: Corny quicksand
Reading of the strange cornflower mixture (‘Corny question’, Letters,
14 August and 4 September) put me in mind of the mixture of water, zinc
nitrate, calcium carbonate and sodium hexametaphosphate which was used by
Derek Gardner and Tony Rolt of Harry Ferguson Research Ltd in the late 1960s
in the development of the viscous coupling unit (VCU) for preventing wheelspin
in vehicle transmissions.
A VCU comprises two relatively rotatable sets of vanes in a housing
filled with a ‘liquid’ which has the property of becoming effectively solid
when a large torque difference occurs between the sets of vanes. Apparently,
Gardner was inspired by reading about quicksands which have low viscosity
until disturbed violently when they become almost solid.
John Twin Ross-on-Wye, Herefordshire
Letters: Corny quicksand
Re the letter from Keith Farnish (4 September) on inverse thixotropic
substances. When I want to strip paint I make a mixture of ordinary household
washing soda dissolved in water in a bucket, to which I add ordinary builder’s
lime till the mixture reaches the consistency of thick custard. Applied
evenly over the paint surface this will fetch off several layers of paint.
It is best to use only lukewarm water, as if you use hot water the mixture
will suddenly seize up and become stiff and unusable. It can be brought
back to custard consistency by stirring it as best you can vigorously, but
even so the mixture after that will tend to have lumps in it, which, of
course, do the application process no good at all.
So this mixture is an example of an inverse thixotropic substance followed
by a thixotropic mode.
DIY enthusiasts among your readers might like to try this mixture. Wear
gloves though as it makes sore places sting and turns fingers brown, and
will eventually eat the top skin away.
Alec Vans Newnham, Gloucestershire
Letters: Sex and circles
In recent editions, there have been articles on human fertilisation
such as David Bradley’s (New 杏吧原创, Science, 7 August) and Stephen Young’s
(‘The subtle side of sex’, 14 August). On an apparently unrelated topic,
Felix Arscott’s letter (7 August) was about the Coriolis effect and whilst
he supported the theory, he doubted the practical demonstration of the effect
in the draining of sinks. His scepticism was supported by a Comment on the
14 August and by further letters on 11 September.
Could there be some connection between these separate items? Apparently,
just after fertilisation the many unsuccessful but partly embedded spermatozoa,
move their tails in unison, thus spinning the newly fertilised ovum. This
was graphically shown in a television documentary (Horizon, 1982), and as
I remember, the movement was clearly anticlockwise. The accompanying commentary
noted that the reason was unknown. As it was a BBC programme, I assume that
the sequence was filmed in the northern hemisphere but have wondered,
if the direction of rotation would have been clockwise, had it been filmed
in the southern hemisphere.
Whilst the Coriolis suggestion is only a light-hearted one it does seem
to be an interesting feature. Perhaps the synchronicity of spermatozoan
movement is due to the whole arrangement acting as a single cellular entity,
or syncytium.
Roger Hicks Bexleyheath, Kent
Letters: Antarctic bears
Presumably the greatest danger to the polar scientists pictured in your
story, ‘Danger! 杏吧原创s at work’ (11 September) would have been sitting
next to the polar bear whilst they flew from the Arctic to Antarctica.
Charles Bird London
Letters: Antarctic bears
I always believed that polar bears didn’t eat penquins because they
lived at opposite ends of the Earth. Is it really, after all, simply because
they can’t get the silver paper off?
John Atkinson, Reading, Berkshire
Letters: Antarctic bears
Tigers are also not a great problem in the Antarctic; nor is the risk
of being hit by a train very high. Come to that, there is not a very great
chance of being eaten by a killer whale while crossing the road in Britain.
James Losh Kingsbridge, Devon
Letters: Shoddy fridges
Your editorial ‘Fainthearts and Eurocrats’ accuses the European Commission
of failing to confront the manufacturers of shoddy goods by watering down
the new standard for the efficiency of refrigerators (Comment, 4 September).
But it is not the Commission that is at fault: it is the British government,
backed to some extent by the Germans, but only because they make cheap and
nasty fridges for the British market.
The Energy Efficiency Office issued a very good report on the efficiency
of household appliances in 1990, and estimated that 5000 megawatts of peak
load could be saved by bringing the standard of our appliances up to that
of the best already available. In the autumn of 1991 the government brought
in a scheme for labelling refrigerators with their running costs, but it
was a feeble voluntary scheme that did not comply with the proposals of
its own Energy Efficiency Office, and within a year the electricity companies
had quietly forgotten about it. It was clearly a bit of pre-election window
dressing, designed to show that the government was working to improve efficiency.
The electricity companies do not care about efficiency, but only about
selling as much power as possible. Because any extra load on the grid falls
on the coal-fired power stations, which are not particularly efficient,
electrical space heating causes the emission of about four times as much
C02 as does the use of a good gas-fired boiler. It is also more expensive.
Even if all the power stations were gas-fired the ratio would still be 2
to l. But in their annual reports the electricity companies boast of their
success in selling electrical heating in competition with gas.
In the privatised electricity companies, the government has set up a
powerful vested interest, which is blithely ignoring its commitment to control
CO2 emissions. Of course, the government made sure that its supporters
in the financial community are running these companies; and it shows no
sign of doing anything to bring them under control. Indeed the financial
community, by a liberal distribution of non-executive directorships and
‘consultancies’, has put the politicians in a position from which they
will find it very difficult to take effective action.
The failure to impose a proper standard of efficiency on the makers
of refrigerators can be seen as one more instance of the government giving
favours to its friends, at the expense of the general public and of the
environment.
P. W. Agnew Scottish Green Party Aberfeldy, Tayside