To help out friends, I sometimes collect a boy from his primary school near Sloane Square. This part of London boasts the most expensive homes in Britain and the local families are served by a crop of ultra-pricey schools. The best known, Hill House, was founded in the 1940s by an eccentric army officer, ‘the Colonel’, who replaced the traditional blazers, caps and ties with a uniform of soft shoes, breeches and cravats inspired by George Mallory’s climbing kit.