OILS. These Useful substances are Ob tained from very different sources and under Orions circtinittances, kirst, animal fats are to be regarded aS Varieties of oil. There are alsd knifed oils more properly so called, as whale and sperMaceti Oil. Secondly, there are the oils of vegetable origin, as those of olives and obtained by pressure, and called fat, fixed; Or expressed Oils, and those pro• Chred by distillation, termed volatile, essential, Cr tetherial Oils. Thirdly, there are yakking oils produced by heat from animal, mineral, and ether bodies, Snell AS .bippel's oil and the. Lastly, there ore certain oils produced by chenifcal action, aS oil of wine, &c. Most fats and expressed Oils consist of by some thernisti called matyarift and steitrin.
Animal Oils.—One of the best known and Most ektensively tilted of these is common whale or train oil, obtained by melting the blubber of the Mina As that with in com merce it is of a brownish colour, rather viscid, and hat a diSagreeable halty Si:dell and taste. Like btlier Oils; it IS Very combustible, and it is largely employed ION the piirpase bf giving light m5'p@rlitdcet! On it Obtained froin an Oily Matter lodgdd iii a body Cavity of the head Of the gperiniteeti Whale: Whert this atiliStaneb is subjected to pre§Stiro its bagg; a ilhatitity Of pare limpid oil is eXpreS8ed and the reSidtie after being Melted, Strained, had belled With li stele solution Of potash; IS Well kittrall by the Mime Of spermaceti; The other anitfial oils are of less iniportalide, Plaid OiLI.-The Vegetable Blittekti Oils nary its their properties? Olive 011 is yellow ish, the tidaiir and taste but alight Linseed Oil is etpresSed froth the Seeds of the common get. When tad heat iS employed in the pres it is More viscid and has a greenish-yet. loW Colour; it it theft balled in commerce cold draiiitt linseed 0i1. Its smell and taste are etreilger and more disagreeable Utah those of olive oil. Linseed oil is largely employed iii Oil painting and in Varnish-intildng. Abitoad Oil 14 of it 1IRlit yellowish colour, more fluid than Mite or linseed Oil; its odour and taste are Very slight. It IS employed soinetiiiiet id soap reedit, and also ih Medicine. CaStor Oil is the expressed Oil of the Seeds of the eaniiiini3. Whets eXproSeedwithout the assistance Of heat, it is transparent and nearly delotirleas. It is Very considerably and becomes Solid when exposed to about 0° Fah. - Solid OilS.----One of the chief bf these is Voroa 0/1. It is 'white, lag a Slight plea• sant smell, and its taste is rather agreeable it melts at Pahr., and of late years it hat been employed in tbap lneking. Paint Oil it of the cotitistente of butter, hod of bn orange yellow rol51ir; its smell is 'agreeable. It Melts at about 103° l'ahr.
Volatile 02 Enentiat fiits.=TheSei oils are fluid at the tishal temperature, hod With few exceptions are obtained by distillation. BSserIL tial oils are distingnithed principally front the expressed oils by the following prepertiet Usually they are More perfectly fluid, MOM totablistible, hare 6.11 aromatic or fragrant
odour, and an atria taste: they are volatile per to Without tlectiMpbsition, and May be dis tilled with water at althotigh their boil ing-paint is Math higher. In Some instances the volatile tilt are ebtailied bypresattre, Out the application of heat : this is the date With the Oils of lemons, Oranges, and bergs Mat. Ili general however they are procurable only by distillation, and thig is effected by putting the herb br bath into it still with water, When the Oil and water are volatilized and condensed together. Like the filed Oils they appear to contain a harder and a softer prin blple; the feigner has been called itearopfdtl, the letter eleapten. The moat iniptirtent Oils of this elaSt are thtige of Purpoitine, Lerimizt, C/ort4 and A/iii6;ids.
Both volatile and fixed 0115 are Very ditten sivelydillithed through Vegetables ; the fernier in alfnett every part of a plant except the cO Lyle &Ma of the seed, and the latter in the Seeds Chiefly, Mit also in their fleshy ebirekin as in the Olive, some palms, and Other plants. Some familida bf plants Oolitic' especially in axed on. Among the Critelferee are PlitiStaA seed, rape heed, and bald Seed Oils, with other species especially cultivated in Ettrope, and Japan, of Which some hallo of late years been imported into this country. Several of the fan:illy of Coinposite secrete oil iiitpiantities large enough to render it desirable to Culti vate them for this purpose alone, at the Sim Flower and Jerusalem Arad:lob: also some SpecieS bf Carlitantus or Bastard Saffron, and also the Verbesifia sativa of India. Acadia saliva yields Mut Oil, and its Seed§ are said to contain snore Oil than any plant introduced into Etirope. Most of the Cucurbitarec also, as the gourd, cucumber, and the mime rout VarietteS, Cultivated especially in India, tiOntain a large proportion of oil, which presSed the east as it formerly was in rope. The floseteetr also store up a large pre portieft of Oil ih the kernels of their fruit, as in the almond, the apricot, as Well as the anon apricot, and alibi. species Of Primes. In the Himalayas oil IS alb expressed from the apricot kernel, and has been sett tb this ebuntry, of a line quality. Among the Amen Mem several species yield oil of good. quality, and in sUfacieht gitantity to repay the expense bf ekpteSsidn, as hazel-nut oil, Oil, and Walnut oil. Besides these poppy oil, ten nut oil (Itypevanthera), oil (Ara Otia),physid-htit olit.latfopha) are The cotton teed yield§ oil, hoa also the seeds bf the tea plant, dApeolally of the specie§ balled Then oleic era, and some of the The imports of the principal oils and bf oil cake for the last two years haVe enabluited to the following quantities :— The linseed, hempseed, and rapeteed oil ported in 11350 amoittited to 3,29,200 gallons.