“ Ordinary or table vinegars, which contain, in addition to acetic acid, small quantities of alcohol, higher acids such as tartaric and succinic, various esters, albuminous substances, &c., are produced solely by acetous fermentation, wood vinegar being only employed in certain arts. Ordinary vinegar has been known from the earliest times, and its power of combining with or dissolving mineral substances caused the alchemists to investigate its preparation and properties. ”

“ Falling on to the shavings, the surface is largely increased, and the fermentation which ensues maintains the temperature at about 37°, and draws a current of air upwards through the shavings, which after a time become covered with the so-called mother of vinegar. If the liquid contains only 4% of alcohol, it is completely converted into acetic acid, but stronger liquors require to be passed through the vat three or four times. Some of the alcohol (and consequently some acetic acid) is carried away by the air which escapes to the top of the vat ”

“ The sides of the vat enclosing the lowest portion are provided with a ring of holes to admit air to the tub; and the vat is enclosed with a tightly fitting lid perforated by a hole through which the liquor to be fermented is admitted and the air drawn upwards from the base escapes. ”