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^\.C ANTICONE. See Amphibole.

ACETIC ACID . Acetites. Vinegar.

M. Cadet a has made several experiments onthe manufacture of sugar-vinegar and the bestproportions of ingredients. It is well knownthat pure sugar dissolved in water will not fer-ment by itself, but if yeast or leaven be added,fermentation is soon established, at first vinous,afterwards acetous. Mucilage, Extract, Fecula , contributed materially to the products of fer-mentation, but M. Cadet has apparently beencompelled in order to simplify the enquiry, topass over very slightly the effects of these sub-stances, and to confine himself to the operationof sugar alone. Iiis results therefore can onlybe considered as affording some approximationto accuracy. To form a simple sugar vinegarhe gives the following as the best proportions.

Sugar .... 12.4.

Leaven or Yeast . 8.

Water .... 86.8

100.0

When a much greater proportion of sugar isadded, a portion of it escapes fermentation, andmay be procured from the vinegar unaltered.Though alcohol is the leading product of thevinous fermentation, and therefore (ceteris pa-ribus) the more alcohol a fermented liquorcontains, the greater quantity of acetous acid itwill produce, yet the addition of alcohol to thefermenting liquor will not encrease the productof acetous acid, and if more than about T ’ T of

* An. Chim. tom. 6!

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alcohol be added, the fermentation is entirelystopped and no vinegar is formed.

In making vinegar in the large way, fromwhatever vegetable material, whether wine, cy-der, grain, carrots, sugar, &c. M. Cadet advisesa previous essay of about 8 ounces of the ma-terial (if dry) with 3 pounds of water and f oz.of yeast fermented completely into vinegar. Tothis is to be added gradually a solution of caus-tic potash of known strength, till the liquor issaturated (as determined by litmus, &c.) andthe quantity of solid potash noted. Then forevery part of potash used he estimates 1.268parts of sugar to have been acidified by the fer-mentation, and hence the saccharine strengthof the materials is found. Then to produce,the strongest possible vinegar without leavingany undecomposed sugar, he proposes so muchsugar to be added to the materials (if deficientin this principle) as will raise the proportion to12.4 per cent, of the whole fermenting mass,which (with the 0.8 per cent, of leaven) pro-duces as above mentioned the most favourableproportions for this manufacture.

The density of acetic acid cannot be dependedon singly as any indication of the strength ofacidity. On this subject M. Mollerat has somevaluable observations. >> The strongest aceticacid that he could obtain, which was quite pureand free from empyreuma, had the specificgravity of 1.063 at 60°Fahr. This was highlyvolatile when moderately heated, and entirelycongealed at about 55°, and did not thaw at72°. A given portion of it saturated 250. ofcarbonat of soda, and its proportion of real acid

YOL. III.

»Ibid. 68.

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