I must disagree with Prof Gray (Letters, 20 February) as to the origin of the rounded shapes of the boulders used in the ancient sport of stone lifting in Ireland. They are unlikely to be glacial erratics. Blocks frozen in glacial ice generally retain their initial angular shape and are not abraded. In contrast, rock fragments carried by rivers or located along marine coasts may be rolled and dragged by currents, forming characteristically rounded boulders, cobbles and pebbles.
Dr Alan Woolley
Weybridge, Surrey
• Millions of us woke up to Friday morning’s result in Gorton and Denton (Green party wins Gorton and Denton byelection, pushing Labour to third place, 27 February) and were given a sense of optimism, excitement and hope that, if our stale and moribund two-party politics is indeed coming to a deserved end, there is a future for compassion, fairness, and social justice rather than division, bigotry and tired nostalgia.
Richard Bryant
London
• Key lesson from the Gorton and Denton byelection: people prefer plumbers to politics professors.
Les Bright
Exeter
• Re question 3 of the Weekend Quiz (21 February) – “the body produces 2m of what every second?” – my background pointed me to metres rather than millions, suggesting a rather hairy result, as opposed to the answer of red blood cells.
John Pye
Southampton
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