Letter
Vines remarks on the falling quality of rivers and wells. As one example, she
says that in Cambridge, jokes are made about the need for stomach pumps after
falling into the River Cam, where popular swimming clubs thrived only a
generation or two ago.
But how much is it a fall in quality and how much is it rising standards and
expectations? There is an anecdote about Queen Victoria visiting Cambridge and,
looking at the Cam at a point below a sewage outfall, asking what the pieces of
paper floating on the river were. “Those, Ma’am,” replied an attending official,
“are messages telling people not to bathe.”
War of the planets
Imogen Holst did indeed obtain a court injunction banning the release of Isao
Tomita’s electronic version of Gustav Holst’s The Planetsin Britain
(Feedback, 10 July) . . . but not quite quickly enough.
I bought Tomita’s LP at a store in Birmingham and still have it. Moreover, I
actually returned my first copy which was scratched, and got another, within
three days. The records were off the shelves by day four so I was dead
lucky.
Laughing burps
J. McGlashan is quite right about burps and carbon dioxide (17 July, p 57).
For a weak acid like carbonic, the acidity is proportional to the square root of
the aerial concentration of gas in contact with water. I estimate that a burp
has about a thousand times the concentration of carbon dioxide as ordinary air
(30 per cent as compared with 0.03 per cent) increasing the acidity thirtyfold,
decreasing the pH from the 5.5 for equilibrium with water to about
4鈥攓uite low enough to affect the nose.
Now nitrous oxide (laughing gas) is physically very similar to carbon dioxide
and is nearly as soluble in water, but cannot make it acid鈥攚hich is why
the administered gas is not an irritant. It would be rather fun to prepare some
“nitrousoxygenated water” in place of soda water. It should behave similarly in
the glass but be burp-friendly and, in sufficient quantity, mirth-provoking.
Snack puzzle
With regard to your recent comment about beef-and-onion flavoured potato
crisps being suitable for vegetarians (Feedback, 26 June): as a vegetarian, it
has amused me for years that crisps of the beef, bacon or chicken variety are
suitable for vegetarians, while the one flavour that is not is cheese and
onion.
Most people are flummoxed by this, until I explain that cheese and onion
crisps actually do contain cheese powder, cheese being non-vegetarian when it is
made using animal rennet. Many brands of cheese are now veggie (made with
vegetable rennet), but I have yet to find a brand of cheese and onion crisps
that is marked as suitable for vegetarians.
Pregnant pause
So, “modern day convention has it that as long as a pregnant woman doesn’t do
drugs, or smoke and drink too heavily, there’s little that can harm her growing
child” (“Programmed at birth”, 17 July, p 27).
Yet for the past nine months I have been warned not to eat soft cheese, or
p芒t茅, or lightly cooked eggs or liver, or vitamin tablets
containing vitamin A.
“Not doing drugs” has extended to taking virtually no over-the-counter drug
without checking with the doctor. No aspirin, no cough mixture, no
antihistamines. A selection of creams and aromatherapy oils is also out of
bounds. If I wanted acupuncture or massage I would have to be careful that my
therapist was trained in the care of pregnant women.
No Jacuzzis, no saunas. Cut down on any squash playing or scuba diving. Don’t
travel in an aeroplane during the last trimester. No changing cat litter without
gloves on. Preferably no gardening without gloves on. Don’t catch German
measles, syphilis, AIDS, chicken pox. Take folic acid for months. Eat well.
Exercise moderately.
My Caesarean is due soon. I could say: think of me enjoying a glass of wine
and a Brie sandwich after the birth鈥攂ut there’s modern-day convention for
breastfeeding mothers to worry about first…
Who is to blame?
Science is about understanding the world; technology is about controlling it.
In many cases, what is commonly called “scientific” research seeks to advance
both our understanding and our control, but that doesn’t render the distinction
pointless, as Philip Ball claims (3 July, p 54).
The fact that most people can walk and talk at the same time doesn’t prove
that walking and talking are the same thing. Ball is right in saying that the
distinction between science and technology is largely irrelevant to the debate
about science and ethics. However, he is right for reasons different from the
ones he gives.
If the question is where to place blame for Zyklon B, the gas used to murder
millions in Nazi concentration camps during the Second World War, the answer is
neither science nor technology. The real question is not what is responsible,
but who.
Iris IDs
I was interested to learn that characteristics of the human iris provide a
reliable method of identification (17 July, p 16).
On the opposite page was a Technofile report of a method for registering
cattle herds
on the Internet designed to save paperwork. Assuming that a cow’s iris is
also virtually unique to the individual, could this not be applied as a secure
distinguishing feature for each animal?
There may be oil
The geologist Colin Campbell may be right to say that oil is running out, but
your correspondent Fred Pearce is wrong not to offer his readers the textbook
response to such a claim (10 July, p 49).
When supplies are abundant and prices are low, oil companies do not find it
worthwhile to spend money on exploration. It’s the old Club-of-Rome resource
fallacy. Forty years’ supply is the sort of level you find claimed for a range
of minerals extraction industries.
In 1974 Eric Drake, the chairman of BP, said in a paper to a Royal Society
discussion on energy in the 1980s: “The annual production rate [for oil] has now
reached the level of the average annual discoveries over the last 25 years 鈥�
The declining reserves will be insufficient to support the forecast demand after
about 1978.”
Remarks like this almost certainly fuelled the overreaction in the West to
the oil embargoes and price rises of the 1970s.
It would be nice to say that the views of one geologist do not make a crisis,
but if they are not properly understood they can make a minor drama into
something much greater.
Last gasp
Might I suggest that there is a straightforward explanation for why No
Smoking Days increase the risk of accidents in the workplace but not of those on
the roads (10 July, p 6)?
Thousands of packets of cigarettes emerge from thousands of glove
compartments once their owners are away from the disapproving eyes of their
fellow workers and back in the privacy of their cars. Nicotine levels are thereby
restored to normal, and accident rates likewise.
Simply beautiful
Ian Stewart’s article on elegant mathematical proofs (“Proof and beauty”, 26
June, p 28) reminds me of a proof in plane geometry whose elegance most will
comprehend.
Given an isosceles triangle ABC (A being the vertex), where side AB = side
AC, prove that angle C = angle B. (The usual proof involves bisecting angle A
and proving that the two smaller triangles are identical.)
Proof: Note two triangles: ABC and ACB. Since AB = AC and angle A is the same
in both, then the two triangles are identical, based upon equality of
side-angle-side. Hence angle B = angle C.
The interesting thing about this aesthetically appealing proof is that it was
generated by a computer. So beauty, even in mathematics, is in the eye of the
beholder, rather than the intent of the solver.
Paddling gorillas
There is little doubt that humans are very comfortable and enjoy being in the
water. Your correspondent Gail Vines’s assertion that “Gorillas hate getting
wet”, may not, however, be entirely accurate (17 July, p 52).
In his book The Magnificent GorillaDon Cousins describes how
gorillas in central Gabon have been observed entering marshes and streams in
search of edible aquatic plants. Moreover, he writes, “the Fang tribesmen of
Equatorial Guinea maintain that they have seen wild gorillas `bathing’ in forest
streams.”
Sydney’s Toranga Park Zoo had to add an electric wire to its gorilla exhibit
a few years ago because the inhabitants used to have a great time wading through
the moat, which was meant to keep them separated from the viewing public.
In fact, gorillas are probably descended from creatures that were
significantly more aquatic in the past鈥攔egular waders in lakes, lagoons
and marshes. This would certainly help to explain the little-known behaviour
described above.