78 LOUIS PASTEUE. 



a ' mother ' cannot be transported from one place to 

 another, or even from one part of the same locality to 

 another. The 'mother,' in fact, must rest immovable. 



Pasteur advised the suppression of the ' mothers.' 

 He recommended an apparatus, which is simply 

 a vat, placed in a chamber the temperature of which 

 can be raised to 20 or 25 Centigrade. In these 

 vats vinegar already formed is mixed with wine. On 

 the surface is sown the little plant which converts 

 the wine into vinegar. The mode of sowing it has 

 been already explained. The acetification begins with 

 the development of the plant. 



A great merchant of Orleans, who had from the 

 first adopted Pasteur's process, and who had won the 

 prize offered by the ' Society for the Encouragement 

 of National Industry' for a manufactory perfected 

 after these principles, has stated that at the end 

 of nine or ten days, sometimes even in eight, all 

 the acetified wine is converted into vinegar. From a 

 hundred litres of wine he drew off ninety-five litres of 

 vinegar. After the great rise of temperature observed 

 at the moment of the formation of the vinegar, and 

 which is caused by the chemical union of the alcohol 

 and the oxygen of the air, the vinegar is allowed to 

 cool. It may then be drawn from the vat, introduced 

 into barrels, refined, and straightway delivered, fit for 

 consumption. When the vat is quite emptied, and well 

 cleaned, a new mixture is made of vinegar and wine, 



