THEORY OF THE FORMATION OF VINEGAR. 21 



between wine and so-called artificial wine. The latter can he 

 made so as nearly to approach, as regards taste and smell, genuine 

 wine, but a connoisseur will at once detect the difference. 



The principal defects of the process of manufacturing vinegar 

 by tEe quick process in general use are not in the method itself, 

 for that, as already indicated, corresponds entirely to the theoreti- 

 cal conditions, and yields as good a product as can be obtained 

 from the raw material used. The weak point of the process is 

 found in the practical execution of it : the losses of material are 

 much more considerable and greater than are absolutely necessary, 

 the consumption of labor is very large, and, as every manufacturer 

 knows from experience, interruptions in the regular process of 

 working are of too frequent occurrence. 



All these disadvantages can be reduced to a minimum, if not 

 absolutely overcome, and it is hoped sufficient hints how this can 

 be done will be found in the following chapters. 



CHAPTER II. 



THEORY OF THE FORMATION OF VINEGAR. 



INDEPENDENTLY of the formation of acetic acid by the so- 

 called dry distillation, the chemical processes by which acetic acid 

 in larger quantities is formed are at present quite well understood, 

 and will be briefly explained as follows : 



As previously mentioned, Dobereiner, in 1822, established the 

 theory of the formation of acetic acid from alcohol, and the pro- 

 cesses taking place thereby may be expressed by the following 

 formula : 



C 2 H C + 2 = C 2 H 4 2 + H S 



Alcohol. Oxygen. Acetic acid. Witter. 



According to the above formula, acetic acid and water are 

 formed by the action of oxygen upon alcohol, and hence the for- 

 mation of acetic acid takes place by a partial combustion or 

 oxidation of the latter. Alcohol and acetic acid are, however, 

 only two members of the process, and that, besides the latter, 



