At school I was slow to grasp the point of algebra. So, it was Mr Yelland, the pottery teacher, rather than the maths master, who first showed me a convincing proof of Pythagoras’s theorem with a pair of scissors. It was elegant and ingenious. That proof, I recently found out, was devised neither by Pythagoras nor Mr Yelland but by an eccentric London bookkeeper called Henry Perigal (1801-1898) in 1830.
Papers at the Ri
Papers include: correspondence; journals of John Tyndall, Louisa Tyndall, Thomas Archer Hirst, Edward Frankland and Lady Claud Hamilton; notebooks and experimental diaries of John Tyndall, personal notebooks of Louisa Tyndall and Anna Hirst; lecture notes; biographical material; Thomas Archer Hirst material: journals and biographical notes; press related material; publications and articles; bound volumes of manuscripts relating to John Tyndall's life, work; poetry written or collected by John Tyndall, valentines and travel notes, portraits, medals.
Catalogue information is currently available on request and a summary of the collection can be found on the AIM25 website.