104 
been analysed by Pallas, who, among other products, found tan- 
nin and gallic acid. They have been employed externally, as 
astringents and antiseptics ; internally, as tonics in intermittents. 
Fruit. The preserved olives which are so admired as a dessert, 
are the green unripe fruit deprived of part of their bitterness by 
soaking them in water, and then preserved in an aromatised 
solution of salt. Several varieties are met with in commerce, 
but the most common is the small French, and the large Span- 
ish olive. Olives a la picholine have been soaked in a solution 
of lime or alkali. Oil. The olive is certainly remarkable as 
a fiuit, from the circumstance of its sarcocarp abounding in a 
bland, fixed oil, which is readily obtained by expression. The 
process for curing it is somewhat modified in different countries, 
but its principle is in all essentially the same. 
141 Prep-vratiox of Olive Oil. In Spain the olives are pres- 
sed by conical iron rollers, elevated above the stage or floor, 
round which they move on two little margins to prevent the ker- 
nel being injured, the oil from which is said to have an unplea- 
sant flavour. Spanish olive oil, however, is inferior to other 
kinds, from the circumstance of the time which elapses between 
the gathering and the grinding of the olives. This arises from 
the number of mills not being in proportion to the quantity of 
fruit to be ground; so that the olives are placed in heaps to 
wait their turn, and in consequence often undergo decomposi- 
tion. An excellent account of the manufacture of French olive 
oil is given by Duhamel du Monceau, in his “ Traite des Arbres 
Fruitiers.” The finest oil is procured by bruising the fruit in 
the mill immediately they are gathered, and then submitting the 
paste to pressure. The first product has a greenish tint, and is 
termed virgin oil. The cake or marc is removed from the press, 
broken up with the hand, moistened with boiling water, and re- 
pressed. The products are water, and oil of a second quality ; 
these separate by standing. The cake which is left is termed 
grignon, and is employed by some as fuel ; others, however, fer- 
ment it, and by the aid of boiling water obtain a very inferior 
oil, called gorgon, which is employed either for soap-making or 
burning in lamps. With the view of increasing the quantity of 
oil, some persons allow the olives to undergo incipient fermenta- 
tion, which breaks dow n the parenchyma of the fruit before they 
are pressed ; but the quality of the oil is thereby injured. Gui- 
