Letters archive

Dan Jones discusses ways to make people moral ( 26 September, p 36 ) and Christian B. Miller asks whether "character education" works ( p 26 ). In part, dilemmas on morality come from a lack of understanding that moral behaviour requires thought. "Moral instruction" is an oxymoron promoted by religious and other groups seeking …

The large collection of Homo naledi fossils found deep inside a cave system in South Africa appears to have been placed there intentionally, suggesting some type of ritual for disposing of the dead ( 12 September, p 8 ). That raises an interesting question. How did this ancient hominin, with a brain half the size …

Listening then developing legislation is better than what we are stuck with in the UK Maureesa Walsh welcomes , perhaps wistfully, the science policy of Canada's new government ( 24 October, p 6 )

Discussing the issues of "lost" memories and therapy, you report me saying that memories that re-emerge spontaneously are more likely to be real than those from recovered-memory therapy ( 10 October, p 8 ). To put the record straight, I did not use the term "recovered-memory therapy" and would never do so. It is a …

It is intriguing to read of the lengths to which scientists go to obtain accurate measurements as, for example, in measuring the Boltzman constant to one part per million ( 3 October, p 38 ). My field is educational measurement. Schools and universities, when marking, for example, a physics exam, don't even use an agreed …

Your leader on metrology rightly emphasised its importance as a fundamental, though little-regarded, infra-technology ( 3 October, p 5 ). The UK has long been a world leader in metrology. So why is the National Physical Laboratory's watt balance in Canada? Why is work on the Planck constant being done there and in the US, …

Stained glass craftspeople thank Gilead Amit for busting forever the hoary myth that the ancient glass found thicker at lower edges of leaded glass tesserae "proved" that glass is "a super-cooled liquid," and slumps at ordinary temperatures ( 5 September, p 30 ). Medieval glaziers deliberately used variations in their hand-blown glass to put functional, …

David Hue and colleagues won an Ig Nobel prize this year for finding that urination takes about 21 seconds in most mammals (Feedback, 26 September ). Should this be supported by follow-up studies, it could prove an invaluable early medical diagnostic for men. If they find that the time required for them to empty a …

You say giraffe vocalisations at 92 hertz are "just within the lower limit of human hearing" ( 26 September, p 17 ). In fact this frequency, F#2 in Helmholz notation, is just within the range of the human voice. The lowest note a bass is normally asked to sing is a semitone below this, F2 …

You say that frequencies below about 20 hertz are "too low for us to hear" ( 12 September, p 36 ). Below these frequencies we don't hear a single musical note; instead we hear the individual vibrations. Think of the sound of motor bikes, helicopter blades or pneumatic drills.The 32 foot stops on large organs …

Given the discussion of the effects of our sonic environment on health, what a pity that Europe's standard mains frequency is somewhere around a G on the musical scale (or Bb in the US), instead of a more healthy A. Perhaps we would have tolerated the mains hum better, and maybe even have actively sought …

Chloe Lambert discusses how the nutritional content of vegetables has changed ( 17 October, p 32 ). Another change is cooking methods. When I was growing up in the UK in the 1960s vegetables were routinely boiled until they were soft. This destroyed organic nutrients, though the cooking liquids were sometimes reused, preserving some minerals. …

You quote a spokeswoman for Shell saying: "We already have an operation with the Russian firm, Gazprom, to explore in the Russian Arctic around Sakhalin Island" ( 3 October, p 7 ). Sakhalin goes only as far north as 54°N or so, not even close to the 66°N used to define the Arctic circle. Les …

Thanks to climate change, trees are now "heading north" ( 3 October, p 42 ). Has anyone warned Macbeth ? London, UK

• We inverted the figures: of the 47 pairs of twins in Tuck Ngun's epigenetic study, 10 were both gay and 37 differed ( 17 October, p 12 ).