AUTOMATIC VINEGAR APPARATUS. 91 



It being in all cases advisable to prepare vinegar with a high 

 percentage of acetic acid most manufacturers now pass the alco- 

 holic liquid successively through three generators. In practice 

 it is recommended to place the generators which are to receive 

 alcoholic liquid of the same content of acetic acid alongside each 

 other, which leads naturally to the division of the generators into 

 three groups. If, for instance, a factory contains 48 generators, 

 each group contains 16 ; group I is charged with freshly prepared 

 alcoholic liquid ; the generators of group II contain the alcoholic 

 liquid which has already passed through those of group I, and 

 group III is charged with the fluid yielded by group II. 



Besides the easy control of the work, this arrangement into 

 groups has another advantage. The generators in which the last 

 remnants of the alcohol of a quite strong fluid are to be converted 

 into acetic acid are best kept at a somewhat higher temperature, 

 and with a suitably arranged heating apparatus and the eventual 

 use of curtains by which the workroom can be divided at will 

 into two or three partitions, it can be readily arranged to convey 

 somewhat more heat to the second group of generators and the 

 greatest quantity to the third. 



The height of the actual workroom of the factory should not 

 be greater than required by that of the generators. The reservoir 

 is placed under the roof of the workroom, while the collecting 

 vessels are either sunk in the floor or placed in the cellar. 



Below is given a description of a periodically working estab- 

 lishment with 24 generators. The generators are arranged in 

 three groups, I, II, and III, the following articles belonging to 

 each group : 



8 generators ; 



1 reservoir; 



1 collecting vessel ; 



8 apparatuses for the distribution of the alcoholic liquid into 

 the generators ; 



Conduits for the alcoholic liquid to be poured in ; 



Conduits for the alcoholic liquid running off. 



For the three groups in common : 



A pump to convey the alcoholic liquid from the collecting 

 vessels to the reservoirs. 



