Letters : W3 for me
St Clement Jersey
It is worth noting that another relatively common pronunciation of (or even
an alternate spelling for) “www” is simply “w3″鈥攆or instance, the WWW
consortium is referred to as W3c
(Letters, 25 October, p 58, and
15 November, p 59).
This makes life far easier when discussing Web pages, although, perhaps a
more sensible solution is simply to refer to the site by its given title.
The use of the “www” in many addresses is unnecessary, since the two “big
boy” browsers (IE and Netscape) will typically cope happily with
http://xyz.com rather than http://www.xyz.com.
Letters : . . . . . . .
Twickenham, Middlesex
Since 1992 when our first wind farms started operating, British sales of
electricity have risen by just short of 2.5 per cent per annum to 298 670
gigawatt-hours in 1996.
In that year our 550 wind turbines produced 505 gigawatt-hours鈥攁bout
0.17 per cent of our consumption.
We may conclude that we would have to build 775 of these idiotic machines
every year just to keep up with the increase in electricity consumption.
That is the folly of trying to tackle problems of emissions on the supply
side. Are we to see all out finest coasts and hills industrialised with turbines
in a pointless symbolic gesture?
Letters : Watts from wind
London
Much of K. H. Green’s diatribe against wind energy is misinformed
(Letters, 29 November, p 61).
Last calendar year, wind turbines fed 486 gigawatt-hours
into Britain’s national grid. Furthermore, the cost of wind energy is now
comparable with the market price for electricity from other sources. The
electricity regulator, OFFER, recently quoted the average regional electricity
company purchase cost as 3.52p per kilowatt-hour. The average price of wind
energy was 3.53p per kilowatt-hour.
As for his statement that windmills are “a joke” because rotating turbines
must always be kept online as a backup, he couldn’t be more wrong. “Spinning
reserve”, as this backup is commonly called, is required to cater for unexpected
outages of the very largest plant on the electricity system. Wind turbines make
absolutely no difference to the amount of spinning reserve needed.
Only if an intermittent source of energy such as wind were to supply more
than 10 to 20 per cent of our electricity would any changes be required to the
running of the system. At this point a very small incremental cost penalty would
arise.
More information on wind energy is available on our Web site www.bwea.com.
Letters : Face facts
Palmerston North, New Zealand
I applaud any project which promotes a wider understanding of natural signed
languages. I do not feel that the MIT project to translate American Sign
Language, as reported (This Week, 15 November, p 19),
is to be applauded. It may
be true that “a camera can pick out the hands more easily when the signer’s face
is not in the background”, but this is to divorce the project from ASL.
The central role of facial expression in signed languages is often not
understood. Many have the naive idea that languages such as ASL or BSL are
“languages of the hands”. This view soon changes when anyone begins to learn or
work formally with a signed language.
Facial expression carries much of the grammar in signed languages, the most
obvious being negation and question forms.
There is a further difficulty with what counts as a word. Small differences
in non-manual features assist in differentiating a sign from other signs with
identical manual features. This is what hearing people so often
miss鈥攆luent signers generally focus their gaze on the face. The manual
component of the language is picked up with heightened peripheral vision and the
face is far more central to the language than most of us realise.
Many everyday signs involve contact between hand and face. In ASL these
include the signs for “today”, “yesterday”, “who”, “when”, “because”, “know”,
and the point of impact can be significant鈥攎aleness is associated
with the upper part of the face and femaleness with the lower. The same hand
shape is used for “nephew” and “niece” but in different position on the
face.
The final sentence of the report on the MIT project is thus far more
significant than it might appear. “Facial expressions are likely to be trickier,
however.” As I understand the literature, facial expressions are crucial.
Letters : Sorting the peas
London
As your article suggests, opinion is varied as to the best method of
measuring airborne particles, or PM10
(This Week, 29 November, p 5). True, the
TEOM method “loses” some of the volatile component of PM10 by heating it to 50
掳C. But to be fair, it does offer the advantage of measuring particulates
under exactly the same conditions wherever it is deployed.
A more important question, though, is what size of particle we should be
measuring. A recent study showed that in a sample of PM2.5 material
(particulates with a diameter of less than 2.5 micrometres), particles smaller
than 0.1 micrometres made up just 1 per cent of the total mass
measured鈥攂ut a whopping 73 per cent of the particle number. Results from
mass-based measuring techniques thus run the risk of being swamped by a very
small number of relatively massive particles.
This is important because of emerging evidence that damage to people’s lungs
is caused by the very smallest fraction of airborne particles鈥攑erhaps
because of their chemical composition, or their greater ability to penetrate the
lungs, or both. Larger particles, which by virtue of their size dominate PM10
measurements, are thought to be relatively harmless.
Measuring PM10 is a bit like weighing a cardboard box filled with a mixture
of cricket balls, golf balls, conkers and dried peas. Fairly straightforward and
easy to do鈥攂ut if it’s the dried peas you’re interested in, the result
doesn’t mean very much.
Letters : Secret ingredient
London
Your correspondent Chris Cradock asks: how about content labelling for
medicines? (Letters, 29 November, p 61).
My child recently took a liking to a liquid vitamin supplement. To me it
tasted of glucose, a substance we do not wish him to consume. There was no
indication on the pack as to whether it was in fact glucose or artificial
sweeteners that were used in this preparation, so I asked the pharmacist who
sold us the product. He had no idea and showed no interest in finding out.
Consumers should be told what the non-active ingredients of all medicines
are.
Letters : Awful lot of coffee
Tony@howl.demon.co.uk
The way your article presents the findings of the University of Exeter on the
energy taken to transport food looks scientific because it gives a clear
numerical comparison between different foods
(This Week, 6 December, p 10).
Unfortunately, it falls into the common trap of measuring the wrong
thing鈥攊n this case, the calorific value of food.
Should I give up coffee because it takes a whopping 177 megajoules of energy
to transport 1 megajoule’s worth of coffee? How much coffee is that anyway?
Dieters are usually told that black coffee with no sugar has negligible
calories, so it must be quite a few cups. Or does the figure count the grounds,
which we throw away?
Clearly, joules is a silly unit for measuring coffee. But not just for
coffee. People cannot live by energy alone鈥攚e also need fibre, vitamins
and minerals.
It must be bad for the environment to transport food many thousands of miles
when there are adequate local alternatives, as indeed David Coley is reported as
saying. Such sensible comments can only be undermined by a table that measures
the usefulness of all food solely by calorific value, inevitably making all
low-energy foods the prime environmental baddies.
Letters : . . . . . . .
Rotherham, Yorkshire
I was not surprised to see Green’s comments about wind farms, since once
again they come from someone who lives just about as far away as it
is possible to get from the very large areas of this country (around the
Yorkshire Ouse and the nearby Trent) blighted by the enormous fossil fuel
stations which supply the rest of the country with electricity.
There seems to be some curious idea that people up here simply cannot see
these. Well, we can. The difference is, of course, that wind farms become
unobtrusive over a distance of five miles or so, whereas these megastations
remain visible over 30 miles or more.
Huge areas of the “tops” of the dark peak are blighted by views of
Ferrbybridge and Eggborough power stations and their effluent, while a nearby
wind farm soon becomes unobtrusive.
Letters : Wrong bay
iinuma@lenz.phys.unsw.edu.au
Your editorial says “. . . mercury waste into Manama Bay in Japan . . . “
(22 November, p 3).
This should be Minamata Bay in Japan. Manama is in Bahrain.
Sorry. Spell-checker blight was at work in the New 杏吧原创 office: A
slip of the finger, and one town becomes another, just like that鈥擡d
Letters : Sexing Teletubbies
London
So baby boys are much more excited by images of other baby boys than by
images of baby girls (In Brief, 22 November, p 29).
Perhaps those readers with young sons could use this finding to determine
which sex each Teletubby really is.
Letters : . . . . . . .
If “w” is pronounced “double-u” why not “hex-u” for “www”?
Letters : Crest of the wave
Randwick, NSW
I was pleased to hear that you found the technology of Energetch Australia
interesting enough to publish
(This Week, 1 November, p 6). It’s always nice to
get exposure for these sorts of ventures. I must point out, though, that the
costs per kilowatt-hour you published seemed to err by a factor of ten or so. No
energy producer in the world (coal included) can sustain prices as low as 0.4p
per kilowatt-hour.
I was a little mystified, also, that you chose only to highlight the
parabolic wall aspect of our technology and not the turbine. The turbine we have
developed is unlike any other operating in the world. Tests have indicated it to
be up to four times as efficient as the Wells turbine, the most commonly used
turbine for wave energy applications. This implies a power generation cost four
times cheaper than conventional wave generators, even before the benefits of the
parabolic wall are considered. In addition, it doesn’t stall like the Wells
turbine does.
Letters : . . . . . . .
Harlow, Essex
I was amused by your latest crop of spell checker howlers
(Feedback, 15 November).
I have yet to see a Microsoft spell checker that knows how to spell Microsoft
or, for that matter, any of the company’s major products.
Letters : Blue Christmas
aprc@pcmail.nerc-bas.ac.uk
I recently wrote a piece for our church magazine. As it was for the last
issue before Christmas, I wrote about the birth of Jesus, and mentioned the ass
and the ox in passing. On checking the text with Grammatik, the word “ass” was
highlighted with the following suggestion: “Avoid this offensive term. Consider
revising.”
Are grammar checkers prejudiced against certain species?
Letters : . . . . . . .
I used to park my car under a carport, sheltered but open to visits from
neighbourhood birds. I noticed each morning feathers stuck to the external rear
vision mirrors, and bird droppings on the sides of the car below the mirrors. I
found that it was a magpie lark taking violent exception to its reflection in
the mirror and attacking it vigorously. The simple cure was to put opaque
plastic bags over each mirror every evening.
Letters : Belligerent birds
South Ascot, Berkshire
The fact that the males of some species of birds would peck at their own
reflections to beat off a supposed rival is well known among ornithologists
(Feedback, 15 November).
Cardinals in the US are particularly known for it, as
are great tits and robins in Britain. However, these are territorial species and
the behaviour tends to be concentrated in the male.
My observations suggest that the way the budgie spends time in front of a
mirror is very different from one of these other birds. Budgies are gregarious
birds, living in a state of semi-perpetual migration in large flocks, with a lot
of social interaction between them. It is this social interaction, including
preening of each other, that is played out with a reflected image in a mirror,
with a very rare touch of belligerence, prompted I suspect by frustration that
the “other bird” will not return the treatment鈥攁nd it is as true of the
female as of the male.
This social interaction will lead some birds to try to find the other bird
behind the mirror, as if recognising the concept of a window that he can see
through but not get through. Others will even go further, in that an object may
be treated as a surrogate mate鈥攐ur pet for example has been observed
actually attempting to mate with a ball in his cage.
Letters : . . . . . . .
Williamstown Massachusetts
I was apparently swayed by anecdotal reports to give too negative a
probability for clear skies in Cornwall. Jay Anderson, the meteorologist member
of the International Astronomical Union Working Group on Eclipses that I chair,
estimates that the chance of seeing the eclipse from Cornwall includes not only
the 3 per cent to 6 per cent chance of clear skies but also the 25 per cent
chance of scattered clouds and even some of the 50 per cent chance of broken
clouds.
There may be as much as a 45 per cent chance of seeing the eclipse, though
people in Cornwall will not have much mobility on eclipse day and the days
before to increase their chances by moving.
We will keep information on the eclipse accessible through our Web page
http://www.astro.williams.edu/IAU_eclipses. 杏吧原创s at the Rutherford
Appleton Laboratory are planning several types of solar observations to be made
during the eclipse from the ground and from the air. The laboratory also has a
site with much eclipse information at http://ast.star.rl.ac.uk/eclipse99/.
See also http://ds.dial.pipex.com/eclipse99page.
Letters : . . . . . . .
Castel Guernsey
Historical weather records indicate a better than 50 per cent chance of
seeing the eclipse in the Channel Islands. The Sun will be totally eclipsed in
Alderney and 99.9 per cent eclipsed in Guernsey, where there should be a good
display of Baily’s beads. Incidentally, it will be the first total solar eclipse
in the Channel Islands for over a thousand years.
Letters : Eclipsed by clouds?
Guildford, Surrey
Jay Pasachoff is right that Cornwall is not the best location to view the
solar eclipse of 11 August 1999
(Letters, 8 November, p 61). However, it is not
the British Astronomical Association which is going to a Channel Island (in fact
Alderney) but the Royal Astronomical Society, a separate and complementary
organisation.
The BAA will be in Cornwall for the eclipse, in recognition of its importance
as a British event. However, we certainly would not recommend Cornwall as a
destination for anyone who has never seen a total eclipse of the Sun and who is
unlikely to be able to travel across the world to see another
(see http://www.star.ucl.ac. uk/~hwm). For all the reasons Pasachoff mentions,
particularly the weather prospects, you will do better by travelling far across
Europe to Bulgaria or even Iran.
If you do risk Cornwall in 1999, be sure to get there two or three days in
advance, and do not go without accommodation or a camp site already booked. Be
prepared for disappointment under a cloudy sky鈥攁nd book your passage now
to Zambia, Zimbabwe or Mozambique for 21 June 2001.
Letters : Elbowed aside
Fakenham, Norfolk
Tom Wright and Martin Lesser are to be congratulated on their reconstruction
of the steering mechanism of the Vasa
(This Week, 22 November, p 19). They need
not have gone to such lengths to show that Ebba During was wrong to suggest that
the crew member with bilateral osteoarthritis of the elbow was the helmsman of
that ship, however. It is absolutely impossible to predict an individual’s
occupation from the presence of osteoarthritis in the skeleton.
To take one simple point, osteoarthritis of the elbow is not that uncommon
and a safe attribution could be made only if this condition occurred in helmsmen
and no others, and, of course, it does not. There are several other reasons to
show that palaeopathologists鈥攅ven those of During’s standing鈥攈ave no
prospect whatever of determining occupation or activity from the skeleton, yet
this hoary old myth survives despite many arguments against it.
But there is another reason to doubt During’s attribution: during the 18th
century there were no specialist helmsmen on board ship and several of the crew
might be deputed to that job. It seems that the coincidence of finding a
skeleton with osteoarthritis of the elbow in the stern of the ship close to the
helm has led to the kind of spurious logic up with which serious scientists
should not put.
Letters : Rule maker
St Louis, Missouri
The origin of the intriguing ideas in “One Law to Rule Them All”
(8 November, p 30)
lies in work on seismology done by Leon Knopoff of UCLA in the 1960s and
1970s, and the figure on page 34 could have come (with a little redrawing) from
his work.
I extended these ideas to two-dimensional systems in a 1986 paper, and then
Per Bak applied them to sand piles and many other problems, but the fundamental
contribution of Knopoff, who was not mentioned, should not be neglected.