Letter
In New Zealand, the introduction of compulsory seat belt wearing for car
drivers led to a reduction in deaths and serious injury in vehicle accidents.
There are still those who choose not to wear seat belts: they are
over-represented in the statistics, with more deaths and injuries. There was no
drop-off in the number of people driving because they had to wear seat belts.
Those who choose not to wear seat belts are also those who are more likely to
drive too fast, take risks, and drive while drunk.
On the other side of the argument, cycling in heavy traffic exposes you to
PM10 particulates (5 August, p 5) and many other pollutants produced by car
drivers. Have the health effects of this been investigated by the British
Medical Association?
An unexpected benefit of compulsory helmet wearing in New Zealand has been a
big drop in cycle thefts. Police will stop cyclists without helmets鈥攚hich
includes most thieves.
Science's mystery
A persistent theme in New 杏吧原创 is the need to increase public
understanding of science, which in part involves countering perceptions of the
scientist as arrogant. Surely a worthy aim, but not one well served by the
approach advocated by Giovanni Carsaniga
(8 July, p 50). In protest at Satish
Kumar’s statements (17 June, p 46), he advocates redefining knowledge as only
that which is produced by scientific method. This is scientific arrogance at its
worst. And isn’t it just another version of “When you have a hammer, all you see
is nails”?
To my way of thinking, the greatest achievement of science is its recognition
of the inherent provisionality of all knowledge. This runs counter to much of
Western (but not Eastern) religious thought, for example. As Robert Pirsig puts
it in Lila: “Scientific truth . . . is provisional. Thus science,
unlike theology, has been capable of continuous, evolutionary growth.”
The “time-tested methods of rational inquiry, logical thinking, careful
collection and sifting of evidence, experimentation if required, and public
scrutiny” that Carsaniga praises are also jewels in the crown of science. But if
they were all that science consisted of, science would be dead in a few years.
As Albert Einstein pointed out: “A theory can be proved by experiment; but no
path leads from experiment to the birth of a theory.” Science would cease its
continuous, evolutionary growth without scientific creativity.
In my opinion, many of us scientists do not place enough emphasis on the way
in which the mysterious process of creativity operates in the everyday practice
of science. This is one of present-day science’s weak points. Maybe it is here
that science has most to gain from a dialogue with other aspects of human
activity鈥攁rt in particular?
This correspondence is now closed鈥擡d
Smuggled aids
Charles Fraser-Smith was by no means the sole “fixer” developing devices to
help allied air crew and agents
(22 July, p 46). Major Charles Clayton-Hutton
published an account of his work (Official Secret, Max Parrish, 1960)
well before Fraser-Smith’s book, and donated his personal collection of escape
aids to the RAF Museum in the early 1970s, together with artwork explaining how
they work.
Another firm involved in producing these devices was EMI, which developed a
way of hiding maps and banknotes inside 78 rpm gramophone records鈥攚e have
a list of officers to whom these were sent. Bartholomew, the Edinburgh-based
cartographic firm, waived all copyright in its maps as a contribution to the war
effort. The games manufacturer Waddington recently donated its archive relating
to the production of escape aids to the British Library.
Your recent Last Word query about collecting conkers in the First World War
(24 June) reminded me of the lady
who rang the museum, asking why she had
collected empty cotton reels “for the RAF” during the Second World War. After
rejecting several ideas, I noticed in our escape and evasion display a cotton
reel with a tightly wound silk map concealed in a groove cut concentric with the
spindle hole.
With a fresh label covering the groove and fresh cotton, the reels would have
been smuggled into POW camps.
Plant doctors
I read with interest Liz Fletcher’s article concerning plants
(1 July, p 26).
Gardeners have long suspected that plant roots secrete beneficial chemicals.
Companion planting has been practised for centuries and many books have been
written on the subject.
In my own experience, the only way to grow rust-free hollyhocks is to plant
wormwood next to them. Will Ilya Raskin’s method now be used to identify
“guardian” and “doctor” species that can be interplanted with crops to make
environmentally harmful sprays unnecessary?
Blimps are best
I am astonished that Helios is being developed as a communication platform
(22 July, p 30) when reliable
and long-standing technology that can do the same
job is available practically off the shelf.
I am of course talking about airships and blimps. The advantages of using
lighter-than-air craft in an environment of guaranteed low wind speed is
obvious.
The engines will only need to run occasionally. This will increase the whole
craft’s lifetime to one easily comparable to geostationary satellites.
Message to Mum
I wish to disagree with the gentleman from the British Post Office
(15 July, p 17) who maintains
that nobody in their right mind (or wanting to hear from
their mother again) would send an e-card for Mother’s Day.
Postman Pat, or his Mum, is seriously behind the times.
Mother’s Day is just one of a wide range of “special days” which the e-card
merchants are keen to push upon us (and no, I haven’t yet figured out how they
will ever make money, but no doubt there is some plot brewing to get us all
hooked and then strike).
This year, I sent my mother in Britain an e-card. And yes, she replied by
e-mail鈥攁nd I quote: “Thank you for the lovely surprise Mother’s Day card.”
I rest my case.
Slug skivvies
Slugs
(29 July, p 34) are also good at removing burned-on food. I once left
some potatoes to boil dry. The smell was nasty, so I dumped the pan upside down
in the garden. It remained there for a few weeks and when I decided to have a go
at cleaning it I found that slugs had already done the job. (Note: the pan was
subsequently washed.)
Since then I have often used this method of cleaning. It is particularly good
for ovenproof glassware that has burned-on brown marks.
Age concern
Your interesting article “Life in the Old Dog”
(22 July, p 36) omitted to
mention the hormone produced by ageing men. Its name? Preposterone.
Lift in harmony
It never ceases to amaze me how emotional some people get about the
explanation of aircraft wing lift (
8 July, p 50 and
29 July, p 66). There was a
long correspondence in these pages a couple of years ago, but it seems to have
snuck back in again.
There are many alternative but equivalent ways of describing the mechanism of
lift: different path lengths and Bernoulli, circulation and the Magnus effect,
deflected downwash and inertial reaction, conformal transformations of cylinder
flow to Zoukowski aerofoils, and so on. All are fundamentally derived from
Newtonian mechanics and the single assumption of trailing-edge-flow closure (the
Kutta condition). To suggest that one of these is the “true cause” and the
others are merely “consequences” or erroneous is fatuous. It often stems from a
misunderstanding of the alternative descriptions.
You might as well argue about the true cause of a body accelerating as it
falls. Is it due to the gravitational force and Newton’s second law, or is it
due to conservation of energy and the loss of potential energy? Which one is
correct? The question is for sophists, not scientists.
This correspondence is now closed鈥擡d
On your bike
A separate network of cycle routes sends out the same message as mandatory
helmet laws: cycling on public roads is dangerous (
22 July, p 3 and
p 16).
As there is no evidence to suggest that separate cycle routes are safer than
normal roads, they are not the answer. A separate network introduces extra
conflict points where it meets the existing network. Better analysis of the
statistics would show that the majority of cycle accidents happen at
junctions.
To make a real impact on the number of collisions we should be tackling the
root causes. We need education to improve cyclists’ and drivers’ skills, better
vehicle design to enhance visibility, and better road and junction design.
Furthermore, you have a 95 per cent chance of survival if hit by a motor
vehicle at 20 miles per hour, as opposed to 50 per cent at 30 mph and 5 per cent
at 40 mph. Sensible, strictly enforced speed limits would go a long way to
reduce casualties鈥攁long with noise, pollution and congestion.
Letter
It is telling that your article cites the unfortunate example of compulsory
seat belt legislation as a model for a similar helmet wearing law. Seat belt
laws have drastic consequences for those outside vehicles, like pedestrians,
cyclists and motorcyclists.
When seat belts became compulsory in Britain there was an increase in fatal
accidents involving pedestrians and cyclists鈥�135 per year and 40 per year
respectively. Similar effects are reported in Australia, New Zealand, Canada and
eight European countries. An internal Department of Transport report in 1985
predicted an 11 per cent increase in injuries to pedestrians, with a general
increase of between 12 and 13 per cent. Recent work suggests that those drivers
in Britain who started wearing seat belts were 11 to 13 per cent more likely to
injure pedestrians and 7 to 8 per cent more likely to injure cyclists.
The environment of threat we experience on our roads was created with the
complicity of many who would now have us wear helmets.