WORK IN A VINEGAR FACTORY. 123 



an injurious influence upon the augmentation of the vinegar 

 ferment. 



Recourse to crossing is most frequently had for the purpose of 

 " strengthening' 7 the vinegar ferment by working weaker alco- 

 holic liquid in the generators of one group generally that which 

 yields the strongest vinegar when their activity diminishes. 

 This strengthening of the ferment can, however, be effected in a 

 more simple and suitable manner by diminishing the quantity of 

 alcoholic liquid poured in at one time and by increasing the 

 draught of air, and the consequent change of temperature in the 

 generators, so that the principal reasons for " crossing the gene- 

 rators" (which many manufacturers consider indispensable) have 

 no force. 



Group-System in Factories with Automatic Arrangements. 



In a factory so arranged that the pourings are at stated inter- 

 vals effected by an automatic contrivance, the group system as 

 described on p. 93 et seq. should be used. The operation of 

 such a factory is very simple. As seen from the description of 

 the arrangement, the generators are divided into three groups, 

 I, II, and III. Besides the generators each group must be 

 provided with a reservoir, which may be designated V, and a 

 collecting vessel 8. (The other component parts, distributing 

 arrangements, and conduits can here be left out of consideration.) 



For the production of 12 per cent, vinegar in such a factory it 

 is best so to prepare the alcoholic liquid for the several groups 

 that 



Group I contains alcoholic 



liquid with 6 p. c. acetic acid and 6.5 to 6.6 p. c. alcohol. 



Group II contains alcoholic 



liquid with .... 9 " " +3.2 to 3.3 



Group III contains alco- 

 holic liquid with . . 12 " +3.2 to 3.3 



Group I having been acidulated with 6 per cent, vinegar, 

 group II with 9 per cent, vinegar, and group III with 12 per 

 cent, vinegar, the fluid running off from group I, after being 

 compounded with 3.2 to 3.3 per cent, of alcohol, is used in group 



