Naturally addictive
Gregory Sams claims that “there is relatively little evidence of addiction or misuse of products within the herbal and supplements market” (1 May, p 32). Surely this is because traditional remedies that are likely to be abused 鈥� cannabis, coca, opium, quat and many more 鈥� are not readily available as a supplement. Natural products only recently abused, such as ephedra, are now joining them.
He is right that it is unjustly difficult to fund testing of herbal remedies. However, just because a product comes from a genuine jungle plant is no proof of its efficacy, and consumers need to be warned that treatments of natural origin might not be 100 per cent safe.
Hot rock cooperation
I can reassure Peter Green that, far from being ignored, the UK’s Hot Dry Rock geothermal project in Cornwall was a key element in the development of its successor, the Integrated European 鈥� not just French 鈥� HDR Programme at Soultz in Alsace (24 April, p 32).
The latter was set up in 1988 to bring together all the relevant European HDR research teams onto one experimental site. It was funded by national ministries and the European Commission and involved a very successful collaboration between French, German, UK and Italian teams.
If all goes to plan, the Soultz project should start to generate electricity early next year 鈥� 27 years after the team at Fenton Hill, New Mexico, first demonstrated the technology of getting useful heat from dry rock. The UK project was built on the pioneering work at Fenton Hill.
It was designed as a full-scale rock mechanics experiment, not an energy producer, and so had a finite life. But it represented a critical step towards the European effort at Soultz, and its contribution is recognised by everyone involved today. Like so many projects, this has been a multinational team effort and the credit needs to be spread widely. See
Wrong pong
Crispin Piney states that silicon rectifiers were used in the DEUCE in the 1950s (1 May, p 33). This seems a bit early for silicon technology, and besides silicon diodes don’t smell much when they burn out.
He was probably thinking of selenium rectifiers, which pong to high heaven when they burn out, as one did when I was a lad and tried to use my Hornby train set power supply to power my first induction coil.
Changing voice
Voice authentication is moving closer all the time, and not just for credit cards (24 April, p 23). What happens with people who have had a laryngectomy? I have, and I speak with the help of a Blom-Singer valve. The air passage in this valve is only about 1 millimetre diameter and it commonly becomes partly or wholly blocked, and remains so until either it clears itself, or I clear it with the help of running water and a good mirror. This means that my voice quite normally varies from a gruff, deep-pitched sound to a silly little squeak, or anything in between. What will voice authentication make of me?
Diet of worms
Reading your article on a diet of worms to help prevent bowel disease (10 April, p 8), one cannot help but think of the consequences of feeding people parasites. Worm eggs would be discharged in sewage, and where raw sewage is piped into rivers and the water used for irrigation the ova would end up on pastures and could infect livestock.
People could also be infected if they drink or swim in water contaminated with Trichuris suis ova. This to me sounds like an unnecessary risk, even if the worms do not survive long in people.
Letter
In 1979, Marc Kutner and I suggested that focused neutrino beams should be considered as a means of interstellar communication. Our article appeared in a short-lived journal called Cosmic Search (vol 1, p 2). At that time, efforts by SETI to search for extraterrestrial life were devoted to radio waves, though optical waves with lasers are now also under consideration.
But given how advanced any civilisation we are likely to hear from would be, extraterrestrials may well have turned to neutrinos instead of electromagnetic communication. The idea seems worth considering.
Neutrino talk
Talking of neutrino communications, Maury Goodman says, “Any intended recipient would have to be in a fixed place for a long time. If they knew they had to do that, you could probably tell them some other way” (17 April, p 36). While this may mean such a system would not be suitable for mobile communications, it is not relevant to what I would see neutrino communications eventually being used for.
I work for an international communications company and if I could go to any of our clients and tell them that they could replace their fixed multiplexors (communications hubs) and hundreds of miles of cables with a single pair of neutrino transmitters and receivers, they would jump at the chance. Not to mention how it could speed up transatlantic communications without laying costly cabling. And come to think of it, houses don’t usually move that much either鈥�
No more males
I am delighted at the news that mammals may be able to generate offspring from two female parents (24 April, p 8). I have long believed that the aggression that may terminate our species is a male characteristic, and that genetic engineers ought to find a way to eliminate the Y chromosome if we are to be saved.
Cruel Cortez
To say that Hern谩n Cort茅z was “horrified by the ritual of human sacrifice”, as Alison Ayres does in the introduction to her article on Xochimilco’s sunken treasure, and to imply that this was his justification for capturing and destroying Tenochitl谩n, reaffirms the biased historical picture we have all been taught and continue to be taught now (10 April, p 50).
The conquistadores were motivated simply by greed and the lust for power in the New World. The traditions of human sacrifice practised by the Aztecs in New Spain pale in comparison to the atrocities carried out by the conquistadores.
To perpetuate the myth that explorers of the New World were wholesome, God-fearing adventurers intent only on exploration does a disservice to those Amerindians who were murdered and to those being taught the history of that era today.
Negative positive
With the continuing problem of negative experimental results failing to be published, and the consequent misperceptions that causes (1 May, p 3), surely there must be a publishing opportunity out there for somebody?
We already have The Journal of Irreproducible Results, why not The Journal of Negative Results?
Fatal fish gas
I was very interested to read the article about three South Korean fishermen who died after inhaling gases from rotting squid (24 April, p 7). A few years ago we were asked by the UK’s Marine Accident Investigation Bureau to investigate a similar tragedy that led to the death of three seamen on a fishing vessel.
A survey of the literature suggested that some of the microbes that cause fish to rot produce hydrogen sulphide, hydrogen cyanide and carbon dioxide under the same sort of conditions as were present on the vessel. Initial trials with fish and seawater mixtures showed that all three gases could be produced under such conditions.
Further trials showed that at temperatures of 45 掳C, it would only take 30 hours for the concentration of hydrogen cyanide and hydrogen sulphide to reach levels that can be fatal within minutes of inhaling the gas. Even at a relatively low temperature of 20 掳C, these gases reached potentially life-threatening concentrations after 68 hours.
I had the salutary experience of presenting our results at a coroner’s court. The final recommendation was that further investigations should be carried out and ventilation systems installed to prevent further tragedies. As far as we know, no funding for such investigations was ever forthcoming.
Fat under fire
Paul Campos makes some interesting and relevant points in his article about obesity (1 May, p 20). It is quite true that some groups are more susceptible to the harmful effects of obesity than others. It is also likely that weight cycling is damaging. Further, there is certainly an element of religious fervour about some people’s approach to this problem.
However, Campos is a lawyer and lawyers want to win their cases, even if that means ignoring inconvenient facts. Most importantly, he does not mention in his article 鈥� though he may in his book 鈥� the question of diabetes. There is no doubt at all that the prevalence of diabetes is increasing rapidly in both developed and developing countries. In 90 per cent of cases this is so-called type 2 diabetes, which is strongly linked to obesity, especially where excess fat is laid down in the abdomen.
This is very likely to shorten life expectancy, especially by promoting coronary artery disease and other problems with arteries. Although this type of diabetes has very largely been seen in the middle-aged and elderly there are now reports of cases in obese adolescents in the US, about 30 years prematurely.
The idea that the obese teenager does not have a health problem is wishful thinking.
For the record
鈥� Our story on the Digital Theatre Systems cinema subtitling system (17 April, p 22) gave the impression that the reverse window rear projection system used with it was also made by DTS. In fact this system, called Rear Window, is a registered product of WGBH in Boston, US.
Agile mountaineer
Alistair Scott describes a mountaineer who in 1780 was so terrified by the manifestation of a Brocken spectre that he fell to his death (The Last Word, 1 May). Presumably he managed to record the phenomenon in his diary while he was falling?
Warbling biologists
Following on from the letters from Leldon Kelly (10 April, p 33) and John Wormell (1 May, p 33), I thought I would add biology’s contribution to the science chorus, the Amphioxus Song, . For even more, see the collection of biology songs at
Batphonics
So Intel high-definition audio captures frequencies up to 100 kilohertz (24 April, p 24). As Donald Flanders and Michael Swann sang in the 1950s: “The Ear can’t hear as high as that, / But it’s sure to please any passing bat!” This Song of Reproduction concludes: “But I never did care for music much, / It’s the High Fidelity.” Do any audio engineers recognise themselves?
Zebra mystery solved
Once more Feedback has raised the issue of the “humped zebra crossing” (24 April). I think you will find that this is simply a camel in pyjamas.