Robins abroad
“Robin the redbreasted thug” (24/31 December), attempts to destroy the legend of the robin (Erithacus rubecula) plucking the crown of thorns from Christ’s brow by claiming that the robin is not native to the Holy Land. The point being made is that nobody would have seen a robin.
I always considered that Israel was part of the Holy Land. Having observed a robin on an ornithological trip to Israel in March 1994, I read the official bird list for Israel and found the robin to be listed as common in Spring, Autumn and Winter.
Of course, it is still just legend 鈥�
Bell breaking
As physicists who have worked for over 25 years as consultants with John Taylor & Company, Bellfounders of Loughborough, we were surprised by the article “When the Great Bell Broke” (17 December).
Modern bell metal contains approximately 23 per cent tin and 77 per cent copper. The 30 per cent tin mentioned would be an alloy close to speculum, which is very brittle. The metal used for Great Paul was not assayed but was certainly of roughly the modern composition.
It is true, as claimed, that blow holes can occur in badly cast bells (which ought to be scrapped). However blow holes would only influence Young’s modulus locally, not globally as the author implies. If they were of much significance the bell would exhibit appalling “warble”, which it does not.
The author is correct in stating that Great Paul was not tuned and that the Quint is about a semitone sharp. However, when he quotes 233 Hz for B flat he is forgetting that the International Convention fixing that frequency was not adopted until 1939. Although the frequencies of Great Paul’s partials do not conform well with modern tuning practice, they are in general agreement with Old Standard Tuning which was in use when it was cast in 1881. Thus the Hum is only a minor 7th below the Fundamental rather than the octave in a modern bell.
Finite-element methods have been in common use in bell research since at least 1980 in Britain, the Netherlands, Canada and New Zealand. They are a routine tool in bell design. In particular they were used by the Royal Dutch Bell Foundry to produce major-third carillon bells. We suggest that Shippen re-runs his finite-element programme using the values of 103 gigapascals for Young’s modulus and 8.85 脳 103 kg m鈭�3 for density. The results should be insensitive to Poisson’s ratio, which is about 0.38.
Papyrus, please
You report the interesting possibility that the reassembly of the fragmentary remains of early manuscripts written on parchment may be facilitated by identifying individual animal skins using DNA analysis (This Week, 14 January).
However, the fragment of the document which you illustrate is clearly on papyrus (also used for many manuscripts from Dead Sea sites), as shown by the pattern of fractures and fibre bundles. The nature of this composite plant material would obviously require a somewhat different approach.
Wild wolves
It is not true, as stated in Laura Spinney’s “Return to the wild” (14 January) that “no documented evidence exists of an unprovoked attack on a human” by a wolf. There is documented evidence that healthy wolves attack humans without provocation.
These attacks appear to be much more common in Europe and Asia. See, for example, a 1926 article in the National Geographic Magazine (p 521) which discusses wolf attacks on humans in Russia. However, wolves also attack humans in North America. For example, in the 1920s a pair of wolves attacked farmers near Chugwater, Wyoming (Wyoming State Tribune Nov. 1, 1920).
Some twenty years later near Chapleau, Ontario, a railway worker was jumped by a wolf while patrolling a section of track. He managed to fight off the wolf until other workers came and killed it. The wolf was examined by a wildlife specialist and found to be in good condition (Journal of Mammalogy, vol 28, p 294, 1947).
Wolves, although they look like dogs, are not amiable, misunderstood animals. They are dangerous and unpredictable predators that will kill docile prey, such as sheep, for the sake of killing, just as dogs will. To reintroduce them into the Highlands is folly.
Wolves being a favourite topic of the media, the last British wolf is regularly slain in their columns, normally by McQueen of Pollochaig in Inverness-shire, and almost always in 1743. Laura Spinney (“Return to the Wild”, 14 January) concurs as to date but shoots rather than, as is usual, stabs the solitary Georgian survivor.
It is of some mild interest to pursue the gory tale of “buckling” and “dirking” backwards through its multitudinous retellings to its origin in Sir Thomas Dick Lauder’s Account of the Great Floods of August 1829, in the Province of Moray, first published in 1830. Dick Lauder’s colourful invention, however, lacked the key element of date. This was supplied by his friends, the notorious fraudsters, John Sobieski and Charles Edward Stuart, in volume 2 of their Lays of the Deer Forest, published in 1848.
No 18th-century evidence for 18th-century wolves in Scotland is known. Wolves, in a word, became extinct in Britain no later than the 17th century.
Linear spaghetti
Your recent letter on Feynman’s joke (14 January) reminded us of the passage in the book No Ordinary Genius (ed. Christopher Sykes; 1994) in which Danny Hills describes his and Feynman’s experiments with spaghetti:
“If you get a spaghetti stick and you break it, it turns out that instead of breaking in half, it will almost always break into three pieces. Why is this true 鈥� why does it break into three pieces? 鈥� Well we ended up at the end of a couple of hours with broken spaghetti all over the kitchen and no real good theory about why spaghetti breaks in three.”
We can only assume that Feynman was not really trying, since when we investigated this profound and fundamental problem in our own kitchen laboratory, not only did we quickly establish the underlying mechanism, but we even went on to formulate the following general rule for linear spaghetti structures:- If a spaghetti stick is uniformly bent until it fractures and ejects a third piece, then the third piece is always ejected outwards from the convex side.
When the spaghetti fractures for the first time the two remaining pieces then spring outwards, and providing there is a sufficiently weak potential fracture site on the opposite side a second fracture occurs, resulting in a third piece being ejected away from the initially convex side.
The third piece cannot be ejected away from the concave side since this would require a second (and lower energy) fracture on the same side as the first fracture, in which case the spaghetti would have fractured at this second site first.
Although I had not known of Feynman’s claim that a plate thrown into the air spinning will make one wobble for every two complete spin revolutions, I was grateful to your correspondent (Letters, 14 January) for pointing out that in fact the plate will make two wobbles to every complete spin revolution, for this reminded me that I first came across this problem while I was an undergraduate in the days when this sort of mechanics was part of every mathematics degree syllabus.
The problem can be found in the exercises at the end of the chapter on “Motion under no forces” in Ramsey’s Dynamics Volume 2, where it is posed in the form, “Shew that a coin thrown spinning so that its plane remains nearly parallel to itself makes two small wobbles to each complete turn”. Ramsey acknowledges his source for this problem to be the Cambridge Intercollegiate Examinations 1902.
As an aide-memoire to those interested in recounting this problem perhaps some more talented reader could improve on “Two spins to a wobble, and we’ll have to squabble”.
Letters to the Editor
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Men in need
I share the scepticism of your reviewer of the book Unequal Treatment: What You Don’t Know About How Women are Mistreated by the Medical Community (Review, 7 January). It is not obvious that increasing attention from the medical profession to the problems of a certain group of the population will increase the health of that group.
On the other hand, if we accept the premise that it will, then we should surely be devoting more resources to those most in need 鈥� men. Men in nearly all countries of the developed world die six years younger than women. Should we not be trying to narrow, rather than widen, this gap?
Forests and fuel
Fred Pearce’s interesting review of the Swedish study, which reported an increase in woody biomass in Kenya as population has increased, misses one important point (New 杏吧原创, Science, 24/31 December). The article gives the impression, perhaps unwittingly, that forests in Kenya are therefore being conserved and are not under threat.
However, one tree is not the same as any other and, while Kenyan farmers continue to plant trees to replace forest cover lost in the past, the natural forests of Kenya are being destroyed at an alarming rate, particularly since the collapse last year of the Kenya Indigenous Forest Conservation Programme (KIFCON).
It is vital to distinguish trees planted for use (which are often exotic) from indigenous forest (which supports most of the biological diversity). Kenya is in the process of seeing its species-rich natural forests replaced with exotic trees planted on farms. This, as Pearce notes, is also happening in Senegal.
It is heartening to know, but not really unexpected, that farmers are capable of managing their fuelwood supplies. The problem lies in the fact that, while they are doing so, the biological riches of their countries’ forests are being lost.
Old discovery?
It is amazing to read, in Andy Coghlan’s article about the European Patent Office upholding the patent which covers the gene for H2-relaxin, that until the researchers in Melbourne isolated the gene, no one knew that relaxin existed (This Week, 28 January).
It is over 20 years since I first thought I knew it existed, since it is the kind of subject which crops up from time to time in orthopaedic literature and papers. My old 1973 edition of Taber’s Cyclopedic Medical Dictionary defines relaxin as “a polypeptide hormone secreted in the corpus luteum during pregnancy, obtained commercially from ovaries of pregnant cows. It has been used as a uterine relaxant and to soften the cervix. Has no oestrogenic or progestational effect”.
Yet now we are to believe that John Coghlan, director of the Howard Florey Institute of Experimental Psychology and Medicine in Melbourne should be granted a patent on the relaxin gene because the discovery of relaxin at his institute was both “novel and inventive”.
It is a pity I can no longer remember the name of the doctor who first told me that my slipped disc all those years ago was caused by relaxin relaxing my ligaments, which was why I looked it up in the dictionary. Inconvenient as relaxin can sometimes be, I feel strongly that no one should be allowed to patent my relaxin gene.
Andy Coghlan writes: In justifying the patent, the European Patent Office said: “It is common ground amongst the parties that until a DNA encoding human H2-relaxin and its precursors was isolated by the proprietor [of the patent], the existence of this form of relaxin was unknown 鈥� In isolating the DNA encoding human H2-relaxin, the proprietor was not preparing a known substance by conventional means, but providing to the public for the first time a product whose existence was previously unknown. This is regarded as inventive whatever the methods used to prepare the product.”
Turtle tales
Your record of a French environment official saying that the Cayman Island Turtle Farm is “a similar ranch operation” to that on the island of R茅union (This Week, 14 January) is far wide of the mark. This gentleman should visit Cayman before making such inaccurate statements.
The Cayman farm has not taken turtles or turtle eggs from the wild since 1978. It is totally self-supporting with eggs now being produced from turtles which were themselves born at the farm. It produces about 1800 turtles per year for local consumption but also releases large numbers of hatchlings and yearlings into the wild every year (26 995 between 1980 and 1991) and is very concerned with turtle conservation.
Small changes
I really must say how disappointed I was at the alarmist tone of the item about biological agents (In Brief, 14 January).
The article failed even to mention the fact that the vehicle for implementing the European Directive on biological agents is the new Control of Substances Hazardous to Health Regulations 鈥� COSHH 1994 鈥� which replaces COSHH 1988. This would have been useful information for your readers and although many of them will know by now about the new arrangements, others might well be confused and alarmed by an anonymous reference to new legislation and an over-emphasis on notification.
I would like to make clear that the new regulations, although they are fairly detailed, introduce very little that is truly novel. Most of the specific provisions they now contain relating to laboratory work are familiar from longstanding guidance. Notification of intended work with biological agents is just one small part of it all and it is a pity that it was highlighted in such a way.
It will in fact apply to very few establishments. Those affected are primarily new laboratories starting up from scratch on a new site, of which there are relatively few and, we predict, a small number that happen not to have worked before with agents in one or other of the hazard groups to which all pathogens/biological agents are allocated.
Finally, while it is true that with any infraction of the law there is the possibility of some sort of penalty, your piece reads as though new draconian measures are now in force and that severe action will now be taken out of hand against those who fail to notify the HSE when they intend to work with biological agents. Some sort of action might well be taken but your writer presumes too much and overstates the case.
It doesn't add up
Feedback (21 January) seems amused that Microsoft Window’s calculator cannot correctly work out 2.01鈭�2 (it gets 0, not 0.01). I have three calculators that give three different answers for the sum 1 + 5%. Not all of them can be right. I have a calculator that cannot do some sums at all. Several recent calculators claim to use proper algebraic notation; I haven’t found one that actually works correctly. One last example: I have only found one calculator that claims to be able to and can calculate 4脳鈭�5 correctly as 鈭�1.
I suppose manufacturers would like to think nobody uses calculators for anything important. Their attitude is made pretty clear (I quote from Casio’s fx-P401 manual, p 7) “In no event will Casio and its suppliers be liable to you or any other person for any damages, including any incidental or consequential expenses, lost profits, lost savings or any other damages arising out of the use of this product.” Casio is a market leader, and the disclaimer is pretty typical.
I’ve collected several examples of manufacturers’ adverts showing their calculators doing things that are impossible to recreate when you take them home. It seems even the marketing departments don’t know what is going on.
Feedback wonders why, in comparison, there is all the fuss about small errors in the Pentium chip. I myself wonder why nobody makes a fuss about the inaccurate, difficult to use, and unreliable gadgets that fill our lives and on which we all depend 鈥� from passing exams to repaying loans 鈥� but which manufacturers refuse to put right.
Feedback is both right and wrong about the Microsoft Windows calculator. If you do 2.01鈭�0.01, it renders 0.00 on the screen but if you invert the result it gives you 100, which is correct. Also, if you take the result 0.00 and subtract 0.01 you will get something like 2.23644783246E-16 which of course, is the error using double precision.
So the conclusion is that the calculator is correct but the interface to Windows is buggy. I hope that you will have some use for these utterly fascinating and important results.