416 THE VEGETABLE WORLD. 
It is aleohol which gives to wines their intoxicating quality. 
annin gives them roughness. This roughness is corrected by 
many finings, which withdraws a portion of the tannin in com- 
bination with the albumen or gelatine employed. The acids are 
acetic acid and the tartaric acid of potassium, or cream of tartar, 
which give to wine its tartness; and this acidity is corrected by 
adding a suitable’ quantity of neutral tartrate of potash, which 
forms with the acetate of potash and bitartrate of potash a salt 
imperfectly soluble, which deposits itself in great part in a 
crystallised state. As the cream of tartar is gradually deposited 
in the tuns or in bottles, it follows that the wines in time lose 
much of their acidity. In aging they lose also much of their 
colouring matter and take the tint which is called pelure d& Oignon 
in France. 
The Prrrosporacem are chiefly trees or shrubs of Australia, 
Africa, New Zealand, Norfolk Island, China, Japan, and the 
adjacent islands. The berries of Billardiera mutabilis are eatable ; 
the fruit is green and cylindrical, becoming a pale amber colour 
when ripe. 
The Olacacew, trees or shrubs, often spiny, are a small order 
consisting of tropical or hardy tropical shrubs of the East Indies, 
New Holland, and Africa, with one of the West Indies, and a few 
of the Cape of Good Hope. 
The Cyrillacee are evergreen shrubs, with simple non-stipu- 
late leaves, all inhabitants of North Ameriea, and of little general 
interest. 
The Evpryats haye been formed into a group of which 
Mr. Myers has published a monograph. They consist of Icaci- 
nacee, evergreen trees and shrubs, formerly confounded with 
Olacacee, from which however they differ in the calyx being 
always small, persistent, unchanging, and never enlarging with the 
growth of the fruit; the stamens always alternate with the petals 
never-opposite ; flowers symmetrical, articulated on their pedicels ; 
consolidated carpels, and axile placentw. The group consists 
evergreen trees and shrubs, natives of tropical or nearly tropical 
countries, chiefly Africa, the East Indies, America, and Australia. 
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