Basic science
Erwin Vermeij discusses criminal attempts to dissolve bodies in acid (5 November 2014, p 44).
It’s worth noting that Santiago Meza Lopez, also known as “El Pozolero” (the soup maker), is believed to have disposed of 300 bodies for Mexican drug cartels by placing them in barrels and adding a strong solution of sodium hydroxide (caustic soda, or lye). After two days he poured out the “soup” and then disposed of the teeth.
A biologist would have used trypsin in a sodium tetraborate (borax) solution. It leaves the bones and ligaments intact, making for a nice mount. I have “kitchen tested” this with great success.
East Meredith, New York, US
For the record
鈥� We should have mentioned that Fred Pearce’s trip to the mangrove forests of Aceh was funded by Wetlands International (20/27 December 2014, p 9).
Radical oxygen
It is certainly true that iron is the commonest mediator of free-radical production (6 December 2014, p 38). But we should bear in mind iron is only the catalyst, the ultimate driver is oxygen.
The potentially carcinogenic properties of this element have hitherto been sorely overlooked, although you can be sure that, should you breathe oxygen-stripped air, you certainly will not die of cancer.
Kenilworth, Warwickshire, UK
Imagine that
I thoroughly enjoyed Anil Ananthaswamy’s article on how to think about higher dimensions (13 December 2014, p 32).
I’m not a mathematician, but maybe extra dimensions are like imaginary numbers 鈥� not real, but necessary for things to work.
Winchester, Hampshire, UK
Safe fusion
Any discussion of the radiological dangers or otherwise of tritium (20/27 December 2014, p 43) must involve context and quantity. The remark “not to be treated lightly” is the key, and one only has to look at the environmental concerns about tritium emissions from the Canadian Candu reactors to see that potential dangers exist.
Although some years in the future, similar or greater concerns might arise when fusion reactors come on stream. While fusion is often claimed to be a safe source of energy, a large reactor could accumulate some tens of kilograms of tritium.
One problem with this is how we can guarantee its complete containment. Any escape and accumulation within the reactor space could be absolutely disastrous, since tritium is as explosive as hydrogen.
Abingdon, Oxfordshire, UK
The third degree
I read Alice Bows-Larkin’s defence of the 2 掳C global climate target with interest, and with dismay (6 December 2014, p 28).
Dismay because it totally fails to understand the nature of politicians. Australia’s current prime minister, a Rhodes scholar at the University of Oxford, came to power saying on record that he thinks human-induced climate change is “crap”.
How are we to get politicians’ hearts and minds to follow Bows-Larkin, especially when doing so will deprive them of votes? Might they be swayed by having to answer to their grandchildren?
More generally, it might help if people’s fear for their jobs, and their children’s jobs and standard of living in the future, can be clearly linked to climate change.
Pacific Palms, New South Wales, Australia
Guardians of the net
When it comes to abuse online, it seems the problem is that the police have too few people to cover it, while internet companies have little desire to police their own customers (13 December 2014, p 20).
So why not call for volunteers? People already volunteer to be special constables in the UK; they might be able to do it. Maybe some name like Internet Guardians would be suitable?
Candidates would be vetted and protected against any “trolls” that might try to get at them, and their work as guardians would be recorded, so that they could not easily abuse their power.
I think many people might be willing to do this, including some who would not normally think of helping the police.
Coventry, West Midlands, UK
Beaver fever
Further to your article on the reintroduction of the European beaver (6 December 2014, p 26), for some years there has been a colony of beavers living and seemingly breeding on the river Otter in Devon.
This has delighted local people, but the Department for Environment, Food and Rural Affairs (Defra) has raised concerns that the animals might carry a tapeworm which could under very unlikely circumstances be transferred to humans via pet dogs. Defra has expressed an intention to capture the beavers and move them elsewhere.
However, experts from the Scottish Beaver Trial, in which 16 animals were recently introduced to rivers in Argyll, have told us it will be extremely difficult to catch the beavers and will be so stressful for them that it is likely to prove fatal.
It seems that as a nation we are happy to ask disadvantaged citizens in less-developed countries to adjust their way of life in order to accommodate the presence of tigers and other dangerous predators, but we are not prepared to accept a harmless vegetarian which is likely to benefit the ecology of the Otter Valley and which is welcomed by the local people.
Ottery St Mary, Devon, UK
Walk first, then run
Christine Duffill questions whether running and walking at the same speed burn the same number of calories (6 December 2014, p 32).
On flat ground, the oxygen consumption of someone running at 8 kilometres an hour is the same as someone walking at the same speed. I’d suggest the situation would be similar at 6 km/h. Since it is difficult to walk much faster than this on the flat, and difficult to actually run more slowly, comparisons at other speeds are not really feasible.
Moruya, New South Wales, Australia
All work and no pay
Your thoughtful and thought-provoking editorial on the place of robotic workers in society left me wondering about the precise motivations of roboticists (6 December 2014, p 5).
Is it a simple desire to make a lot of money, irrespective of consequences? If so, a simple and direct opposition to their development can be mounted.
Or do these engineers still nurture that once widely quoted mantra about releasing humanity from the drudge of everyday tasks to permit greater leisure and cultural activities?
If it is the latter, roboticists need to clarify how such activities will be paid for, and how to ensure that the low-wage workers their robots displace will still be able to earn money in our society.
Unless something is done radically to reverse the increasing gulf between rich and poor 鈥� wider in the UK now than in Victorian times 鈥� the sort of robotic developments to which you and Mark Harris refer (p 21) can only add to the problem.
Glasshouses, North Yorkshire, UK
Pluto has airs
鈥� Our anthropocentrism got the better of us. We should have said “a breathable atmosphere”.
Pluto has airs
Your article about the birth of habitable moons in astronomic collisions states that “previous studies suggest that a world must be at least a fifth of Earth’s mass to sustain an atmosphere” (22 November 2014, p 19).
But I and my students and colleagues at Williams College and the Massachusetts Institute of Technology, as well as other scientific groups from Boulder and Paris, have long been studying Pluto’s atmosphere.
Pluto has only 1/500th the mass of Earth 鈥� which played a big role in promoting it to its own class, the first plutoid and one of only half a dozen named dwarf planets designated so far.
Williamstown, Massachusetts, US
American work
John Davnall asks whether 200 million people would be sufficient to produce all the products and services needed for a North American lifestyle (6 December 2014, p 32).
It does, of course, depend which North Americans he has in mind. Mexican farm workers and Texan oil barons have very different lifestyles but let’s suppose he means an average American.
I think it’s clear that given mechanised mining, automated factories and computerised services, an adequate production of goods and services would be entirely possible. It wasn’t so long ago that the US produced the majority of its own goods.
But there’s a big uncertainty. Today a large proportion of the work done in developed economies is not about delivering goods and services to people but about competition. The market provides a constant flow of “different not better” products, and marketing and sales work to persuade people to buy them. How much of this should figure in answering Davnall’s question?
An orthodox economist would declare this question off limits. But a green economist, or anyone who has read the latest Intergovernmental Panel on Climate Change report, will know that the correct answer is “as little as possible”.
With a less frenetic economy would come less frenetic lives and less environmental impact per head. Who knows, we might even provide decent lives for the 7 billion people currently inhabiting the planet.
London, UK
Laser treatment
鈥� The laser is housed in a box underneath the train that safely contains the light. Details are available in this online report: .
Laser treatment
Douglas Heingartner writes about the development of a laser for blasting leaves off railway tracks (6 December 2014, p 23). But where does the reflected light go?
A piece of litter on the rail, say the reflective foil from a chocolate bar, could send it anywhere, and a laser beam powerful enough to destroy a leaf could cause permanent blindness if it hits someone in the eye. Presumably LaserThor, the company that built it, has thought of this. How does the company ensure safety?
Crawley Down, West Sussex, UK
Packing for Europa
I agree that searching for life on Europa should be an urgent priority, but I wonder why we don’t try to investigate the inner workings of a body covered in unstable ice by listening to it.
We might do this from very far away using lasers, similar to the way that one can eavesdrop on a conversation by measuring the deviation of a laser reflected off a minutely vibrating surface in the room, such as the window.
Who knows what we might find? Perhaps Europa is alive with a cacophony of whale-like megafauna calling to one another across a dark 100-kilometre-deep ocean. It would be a real achievement to hear them without setting foot on Europa.
Venice, California, US
Packing for Europa
You report that the only way for your proposed Europa CubeSat probe to send data home is to await the arrival of the larger Europa Clipper spacecraft (6 December 2014, p 42).
But how powerful a transmitter could be packed into a CubeSat if nothing else was there? Perhaps a second CubeSat could follow the first to act as a relay. So long as it could still tune into signals from the first one, it could follow quite a long way behind. This trailing CubeSat could relay data direct to Earth, or perhaps to the nearest NASA or ESA spacecraft.
Blawith, Cumbria, UK