On 4 June 1855, Major Henry C. Wayne boarded the USS Supply in New York harbour with orders to sail to Egypt and buy camels for the United States Army. Secretary of War Jefferson Davis had convinced Congress that camels, not horses, were the answer to moving supplies across the arid American Southwest. The animals performed brilliantly in field trials, but the soldiers hated them, the horses panicked, and the Civil War ended the experiment before it could prove itself. Decades later, feral camels still wandered the Arizona desert. Seventy-one years earlier, on 4 June 1784, Élisabeth Thible became the first woman to fly in a free hot air balloon, travelling four kilometres over Lyon whilst singing operatic arias. In 1411, King Charles VI of France, who occasionally believed he was made of glass, granted Roquefort-sur-Soulzon an exclusive cheese-ripening monopoly that remains protected today. On 4 June 1913, suffragette Emily Davison stepped onto the Epsom Derby racetrack and was struck by the King’s horse; she died four days later, never seeing the voting rights she fought for. And in 1996, the Ariane 5 rocket exploded 37 seconds into its maiden flight due to a software conversion error, a £500 million lesson in reusing code without checking the specifications.