The French pharmacist Jean-Baptiste François (1792-1838) from Châlons-en-Champagne (until 1997 Châlons-sur-Marne) invented a method in 1836 to control the sugar content before bottle fermentation of champagne allowed. This made it possible at Dosage to precisely determine the "Liqueur de tirage" (filling dosage). This method became known as "Réduction François". Up to this point, at least 50%, and in extreme cases even 80%, of the bottles burst due to the excess pressure. At that time, the extremely expensive champagne was only affordable for the nobles and wealthy.