"In September 1873 the Germans, who had been occupying sixteen départements, finally left the country. Showing remarkable resilience, the French had discharged the entire five-billion-franc indemnity in a little more than two years. These reparations had been paid so promptly thanks largely to the profits from a booming wine industry, since Louis Pasteur had discovered that pasteurizing wine — briefly heating it to fifty-five degrees Celsius to kill off the microscopic organisms — made it last longer and travel better. The result was an increase in exports to countries such as Britain and America. French art as well as French wine looked like it was beginning to travel well."