Vanity Fair cranks

SIR – The first steam-powered roundabout may not have appeared until 13 years after Vanity Fair was published (Letters, September 5) – but the roundabout’s galloping horses were not invented until 1885, when my great-grandfather, the showman Henry Thurston, patented the overhead crank action.

The family story is that he worked it out using his wife’s hairpins.

Jenny Selby-green

Chipping Norton, Oxfordshire