The Irishman was the first person to prove the dangers of greenhouse gases and the need for hygiene in medicine. As his life’s letters are published, Ailin Quinlan learns that Tyndall was a fearless ambassador for science

TONY PROCTOR (Letters, October 7) appears to believe that a Catholic ethos in schools tends to stunt high performance in mathematics, science and technology and that more generally it is inimical to a true spirit of educational inquiry.

PASTEUR discovered bacteria and then developed pasteurisation; Jennings discovered vaccination and Fleming penicillin - these were three giants of medicine.