Letter: Shifting sands

Sir: The correspondence (about the formation of ripples on beaches) based on scientific study (2 August) fails to explain my observations, made at various seasons over 25 years, of the extensive sandy bay at Mawgan Porth in Cornwall. Heavy surf and high winds guarantee smooth sand at low tide. A dead calm leaves the sand corrugated. Explanation please.

Yours sincerely,

T. G. MERCER

Flamstead,

Hertfordshire

2 August