360 ‘ AMPELIDEZ. 
O%, stearic acid and palmitic acid, the first named acid largely 
prevailing. The crystals of erucic acid melt at 34° C. ; by means 
of fused potash they may be resolved into arachic acid, C?° H*® 
O?, and acetic acid, C? H* 0%. The seeds further contain 5 to 
6 per cent. of tannic acid, which also exists in the skin of the 
fruit. Wine is of a very complicated composition. Inanoldred 
wine, the following substances have been found in 1,000 parts:— 
Water 878, alcohol, containing traces of butyric and amylic 
alcohol, several aldehydes, and the bouquet composed of acetic, 
capric, caprylic, and cenanthic ethers, and essential oil 100. 
Sugar, mannite, glycerine, mucilage, gums, colouring matter . 
or cenolin, fatty matter, nitrogenous matter or ferment, tannin, 
carbonic acid, acid tartrate of potash, tartrates, racemates, 
acetates, propionates, butyrates, lactates, citrates, malates, 
sulphates, nitrates, phosphates, silicates, chlorides, bromides, 
iodides, fluorides, meconates; potash, soda, lime, magnesia, 
alumina, oxide of iron, ammonia 22. Pasteur has recorded the 
presence in all wines of gum combined with phosphate of lime. 
(Un. Pharm., 1869.) Ludwig that of trimethylamine, and 
Lebaigne the frequent presence of manganese (Un. Pharm, 
1870.) 
G. Baumert has found that boric acid i is contained in Goren 
French, and Spanish wines, and in the leaves and tendrils 
of the grape vine. (Ber. 21, 3290.) 
The aroma or bouquet of wines is due to certain essential oils, 
specially belonging to each kind; the vinous odour is due to 
an oil or ethereal principle which has been isolated by Liebig 
and Pelouze and named cenanthic ether, This oil, which exists 
only in small quantity, appears to be formed during fermen- 
Peete > Teale 
tation Fauré thinks it is derived from the skin of the 
ripe fruit.. Berthelot has isolated the bouquet by shaking the 
wine in a vessel of, erhon acid gas with ether freed from _ 
air by passing . sthrough it. ‘The ether on eva- 
in a current of eubouls acid gas gives an extract 
| possessing gee vinous odour and Sieve et of the wine. 
Dorvau 
