first dirigible was 25 m (8½ ft) long and contained 180 cubic metres (6400 cubic feet) of hydrogen gas beneath which he suspended a 3½ hp petrol engine. On 18 September 1898 he took off from the jardin d’acclimatisation in the Bois de Boulogne and promptly ended up in a clump of trees. Know-all bystanders had advised him to take-off downwind. Two days later he was back, this time rising effortlessly into wind to complete a figure of eight 400 m (1300 ft) above an astonished, cheering crowd. ‘Le Petit Santos’ — for he weighed just 49 kg (108 lb) — was an instant hero.