VINEGAR 



1075 



The three ingredients should be very pure. The proportion of product varies with 

 that of the constituents, as we see from the following results of experiments, in which 

 300 parts of mercury were always employed, and from 400 to 450 of water : 



Sulphur 

 114 

 115 

 120 

 150 



Potash 



75 



75 



120 



152 



Vermilion 

 obtained 



. 330 



. 331 



. 321 



. 382 



Sulphur 



120 



100 



60 



Potash 

 180 

 180 

 180 



Vermilion 

 obtained 

 . 245 

 . 244 

 142 



VERT DE GUIGNET. See MITTLER'S GBEEX. 



VICUNA or VICUGNA. Llama vicugna. A variety of the Llama of South 

 America. 



VINE BRACK. A black procured by charring the tendrils of the vine and 

 levigating them. 



VINE DISEASE. O'idimn Tuckeri. The disease which has recently ravished 

 the vines of the South of Francois attributed to the Phylloxeravastatrix. See WINES. 



VINEGAR. All liquids which are susceptible of the vinous fermentation are 

 capable of yielding vinegar. A solution of sugar is the essential ingredient, which is 

 converted first into alcohol, and subsequently into acetic acid. The liquids employed 

 vary according to circumstances. In this country the vinegar of commerce is obtained 

 from an infusion of malt, and in wine countries from inferior wines. 



The oxidation of alcohol is remarkably facilitated by the presence of nitrogenised 

 organic bodies in a state of change, called ferments ; hence the process is frequently 

 termed acetous fermentation. Now, although in most cases the presence of these fer- 

 ments curiously promotes the process, yet they have no specific action of this kind ; for 

 we have already seen that, by exposure to air in a condensed state, alcohol, even when 

 pure, is converted into acetic acid ; and, moreover, the action of oxidising agents, such 

 as chromic and nitric acid, &c., is capable of effecting this change. 



However, in the presence of a ferment, with a free supply of air, and at a tem- 

 perature of from 60 to 90 Fahr., alcohol is abundantly converted into acetic 

 acid. 



At the same time that the alcohol is converted into acetic acid, the nitrogenised and 

 other organic matters undergo peculiar changes, and often a white gelatinous mass is 

 deposited, which contains vibriones and other of the lower forms of organised beings, 

 and which has received the name of mother of vinegar,' 1 from the supposition that the 

 formation and development of this body, instead of being a secondary result of the 

 process, was really its exciting cause. 



1. WINK VINEGAR. ( Vinaigre, Fr. ; Weinessig, Ger.) Wine vinegar is made of the 

 best quality, and on the greatest scale, at Orleans in France, out of wines which have 

 become more or less acidulous, and are, therefore,- of inferior value. When the 

 vinegar is made from well-flavoured wines, it is preferable to every other for the use 

 of the table. The old method pursued in the vinaigreries consists merely in partially 

 filling a series of large casks placed in three or four ranges over each other, in a 

 cellar warmed with a stove to the temperature of 85 Fahr., with the wine mixed with 

 a certain proportion of ready-made vinegar as a ferment. Low-roofed apartments are 

 the most suitable ; when there is a high ceiling it is necessary to elevate the 'mothers,' 

 in order that they may occupy the higher strata of warm air. This trouble is dis- 

 pensed with when the roofs are low. Experience has proved that in high-roofed 

 apartments, where the tuns are placed at different levels, the uppermost work off 

 quicker and better than the others. More wine is added, in successive small portions, 

 as fast as the first has become acetified, taking care that a free ventilation be main- 

 tained, in order to replace the carbonic acid produced by fresh atmospheric oxygen. 

 In summer, under a favourable exposure of the windows and walls of the fermenting 

 room to the sun, artificial heat is not needed. .Each cask is of about 60 gallons' capa- 

 city, and into each cask of the set is poured ^rd its capacity of vinegar, to which 2 galls, 

 of wine are added, and weekly, afterwards, 2 galls, more. About 8 galls, are drawn 

 off at the end of four weeks as vinegar, and then successive additions of winearemade 

 as before to the casks. These are laid horizontally in rows upon their gawntrees, and 

 are pierced at the upper surface of the front end with two holes: one, called the eye, is 

 two inches in diameter, and serves for pouring in the charges through a funnel; the 

 other is a small air-hole alongside. The casks should never be more than rds full, 

 otherwise a sufficient body of air is not present in them for favouring rapid acetification. 

 At the end of a certain period, the deposit of tartar and lees becomes so great that the 



1 This substance has been supposed by some to be a fungus, and has been described by Mulder 

 under the name of Mycoderma aceli, or vini, 



3z2 



