282 | ORD. XVI. Sepearice: OLEA EUROPA, 
. The varieties of this tree are numerous, distinguished not only 
by the form of their leaves, as already noticed, but also by the shape, 
size, and colour of the,fruit; as the large Spanish Olive, the small 
oblong Provence Olive, the oblong dark green Olive, the small 
roundish white Olive,® (Aglandau) the large fleshy or Royal Olive, 
the large round Olive, (Ampoulan) the small round reddish black 
Olive, and the small fragrant or Lucca Olive. Of these, the two 
first sorts, when pickled, are.well known to us by the names of 
Spanish and French Olives, which to many are extremely grateful, 
and have been supposed to excite appetite and to promote diges- 
tion. Pickled Olives are prepared from the green unripe friitt; 
which is repeatedly steeped in water, to which some add alkaline’ 
salt of quick lime, in order to shorten the operation; for when 
macerated in water only, the Olives require a long time before 
their bitterness is sufficiently extracted; after this they are washed 
and preserved in a pickle of common salt and water, to which an 
aromatic is sometimes added. 
The principal consumption of Olives is in the preparation of the 
common sallad oil, or oleum olivarum of the pharmacopeeias, which 
is obtained by grinding and pressing them when thoroughly ripe: 
the finer and purer oils issues first by gentle pressure, and inferior 
sorts on heating the residuum, and pressing it more strongly. The 
best Olive oil is of a bright pale amber colour, bland to the taste, 
and without any smell: it becomes rancid by age, and the sooner, 
if kept in a warm situation: by cold, at the 38 degree of Fahr. 
therm. it congeals, and does not become rancid if kept in a degree’ 
of cold equal to the freezing point of water.* All the mild ex- 
pressed oils of vegetables are nearly of the same nature; a pre- 
_ ference however, in the opinion of Dr. Cullen, should be given 
to the most fluid, and hence the oil of olives, and that of almonds, 
are most commonly directed for internal use. Oil, in some shape, * 
forms a considerable part of our food, both animal and Oe iS 
» This variety affords the best oil. 
© Muschenbroeck, Phil. Nat. tom. ti. p. 616. 
