F.TJ110PEAN OLIVE-TUEE. 379 



cases, snuff-boxes, &c. Tiie wood of the roots, which is agreeably marbled, is 

 preferred to that of the trunk. On account of its hardness and durability, the 

 wood of this tree was anciently used for the hinges of doors ; and, before metal 

 became common, it was selected by the Greeks for the images of their gods. 

 From its resinous and oleaginous nature, the wood of this tree is exceedingly 

 combustible, and burns as well before, as after it is dried. There exudes from 

 its wood a gum, which is sometimes sold for gum-elemi. There is also extracted 

 from this tree a substance called o/inuic. The bark contains a bitter principle, 

 and is regarded as tonic and febrifugal. The leaves are astringent. 



But the chief value of this tree is the oil produced from its fruit, which is used 

 as a substitute for butter, in all the countries where it grows. It is contained in 

 the pulp only, as before observed, whereas, most other fruits have it in the nut 

 or kernel. The proper time for gathering olives for the press is the eve of their 

 maturity. If delayed too long, the next crop is prevented, and the tree is produc- 

 tive only in alternate years. At Aix, where the olive harvest takes place early 

 in November, it is annual ; but in Languedoc, Spain, and Italy, where it is delayed 

 till December or January, it produces fruit but once in two years. The quality 

 of the oil, also, depends upon the gathering of the fruit in the first stage of its 

 maturity. It should be carefully plucked by the hand ; and the whole harvest 

 completed if possible in a day. To concoct the mucilage, and allow the water to 

 evaporate, it is spread out, during two or three days, in beds three inches deep. 

 The oil is obtained by simple pressure, in the following manner : The olives are 

 first bruised by a mill-stone, sufficiently hard as not to break the kernels, and 

 are then put into sacks of coarse linen, feather-grass, or of wool, and subjected 

 to heavy pressure, by which means the most fluid and the best liquor is forced 

 out, and is called virgin-oil. It is received into vessels half filled with water, 

 from which it is skimmed, and put up into tubs, barrels, and bottles, for use. 

 Several coarser kinds of oil are afterwards obtained, by adding hot water to the 

 bruised fruit. The best olive oil is of a bright pale-amber colour, without smell, 

 and bland to the taste. Kept warm, it becomes rancid, and at 38 F. it congeals. 

 It is of the same nature as all mild expressed vegetable oils ; of these, the most 

 fluid are preferred, and hence the oils of olives and almonds are those chiefly 

 used in medicine. One of the most esteemed kinds of oil is that produced at Aix 

 {Huile (TAix en Provence.') Florence Oil is also a fine kind, imported from Leg- 

 horn in flasks surrounded by a kind of network, formed of the leaves of a mono- 

 cotyledonous plant. These are the kinds of olive oil in most frequent use at the 

 tables for salads (hence they are called Salad Oils.) Lucca Oil is imported in 

 jars holding about nineteen gallons each. Genoa Oil is a fine kind. GalUpoU 

 Oil is imported in casks ; and constitutes the largest portion of the olive oil im- 

 ported into England. Sicily Oil is of an inferior quality. Spanish Oil is the 

 worst. The foot deposited by olive oil is used for oiling machinery, under the 

 name of Droppings of Sweet Oil. Olive oil consists of 



Parts. 



Oleine, 72 



Margarine, 28 



In cold weather, the latter constituent congeals in the form of white or yel- 

 lowish globules.* Oily substances do not unite with the contents of acid stom- 

 achs; but to healthy persons they afford much U(Mn-ishment. and medicinally 

 are supposed to correct acrimony, to lubricate, aiul relax. Olive oil is applu'd 

 externally to bites and stings of poisonous animals, and to burns alone, with 



* See Percira's Treatise on Food and Diet, p. 86. 



