4. Fermented oil is obtained in the departments of Aix and Montpellier, by leaving the fresh olives in heaps for some time, and pouring boiling water over them before pressing the oil.  But this method is very seldom put in practice, for the olives during this fermentation lose their peculiar flavor, become much heated, and acquire a musty taste, which is communicated to the oil.

The fruity flavor of the oil depends upon the quality of the olives from which it is pressed, and not upon the method adopted in its preparation,”—­(French “Journal de Pharmacie.”)

The price of olive oil is sufficiently high to lead to its admixture with cheaper oils.  The oil of poppy seeds is that which is usually employed for its adulteration, as it has the advantage of being cheap, of having a sweet taste, and very little smell.  M. Gobley has invented an instrument which he calls an areometer, to detect this fraud.  It is founded on the difference between the densities of olive oil and oil of poppies.

The imports, which in 1826 were only 742,719 gallons, had risen in 1850 to 5,237,816 gallons.  The following figures show the progressive imports and consumption:—­

Imported.     Retained for home consumption.
gallons.         gallons.
1827        1,028,174        1,070,765
1831        4,158,917        1,928,892
1835          606,166          554,196
1839        1,793,920        1,806,178
1843        3,047,688        2,516,724
1847        2,190,384               —­
1848        2,541,672               —­
1849        4,274,928               —­
1850        5,860,806               —­
1851        2,898,756        2,749,572
1852        2,242,296        1,066,400

The imports of olive oil into the port of Liverpool were 9,815 tuns in 1849, and 10,038 tuns in 1850.  It was brought from Manila, Malaga, and Corfu, but chiefly from Barbary, Palermo, Gallipoli, and the Levant.  In 1850 we imported from France 259,646 imperial gallons of olive oil, officially valued at L34,638; the average in ordinary years is only about 20,000 gallons from the continent.

ALMOND OIL.—­To the south of the Empire of Morocco there are forests of the Arzo tree, which is thorny, irregular in its form, and produces a species of almond exceedingly hard.  Its fruit consists of two almonds, rough and bitter, from which an oil is produced, very excellent for frying.  In order to use this oil it requires to be purified by fire, and set in a flame, which must be suffered to die away of itself; the most greasy particles are thus consumed, and its arid qualities wholly destroyed.  “When the Moors gather these fruits they drive their goats under the trees, and as the fruit falls the animals carefully nibble off the skins, and then greedily feed.

The oil of almonds is more fluid than olive oil, and of a clear, transparent, yellowish color, with a very slight odor and taste.  It is occasionally employed for making the finer kinds of soap, and also in medicine.