Page:The New International Encyclopædia 1st ed. v. 14.djvu/921

* OLEANDER. 787 OLENELLUS. The charcoal obtained t'ruin tlio tender, light wood is Used iu Algeria in the nianul'aeture of powder. The propagation of the plant is readily elfected by layers and cuttings. The cuttings are taken from leading shoots, potted singly, and phjced iu a warm frame. A very common prac- tice is to start the roots of the cuttings in bottles of water and to pot them afterwards. OLEARIUS, o'lila'rf-ns, Ao.M (clOOO-Tl). A German author, who introduced Persian poetry into the literature of tlic seventoenlli century, lie was born at Ascliersleben; Latinized his fam- ily name Oel.schlilger ; and studied at Leipzig. In 1;33, with the jioet Fleming (q.v.), he was sent to Russia and Persia with an embassy from Frederick IlL of Holstoin-Ciottorp, as secretary and counselor, but more especially for scien- tific and linguistic research. He made sev- eral valuable maps; studied the customs, litera- ture, and language of Persia : an<l became the greatest Persian scholar of contemporary Europe. He was a member of the famous literary associa- tion the Fruchthrincjende (lesellschaft, and an elegant juose writer. His fame rests on his Be- schreihung der nvueii oricntalischen Reise (lfi47, translated into French and Dutch, and in an English version, lOUl), a work valuable alike as a literary production and as a source of scientific knowledge, Olearius also made a rather free, yet forcible and adequate, version of Saadi's Gulistun. under the title of Porsianisches Jiosen- thal (1654 and 1660). Consult: Grosse, Ad-tim Olearius (Aschersleben, 1867), and the sketch "Olearius," by Ratzel, in the Allgemeine deutsche Biographie. OLE'AROS. The ancient name of Antiparos (q.v.), one nf the .Cyclades. OLEASTER. A shrub. See El.eagnus. OLE BULL. See BiLi,, Ole Borxemanx. OLE'FIANT GAS. See Ethylene. OOiEIC ACID (from Lat. oleum, oil), C,,- H;i,Oj . A colorless liquid of an oily consistence, devoid of smell and taste, and (if it has not been exposed to air) exerting no action on vegetable colors. At low temperature it solidifies to a firm, white, crystalline mass, and in this state it undergoes no change in the air; but when fluid it readily absorbs oxygen, becomes yellow and rancid, and exhibits a strong acid reaction with litmus paper. The melting-point of the pure acid is 14° C. (57° F.). It is not a volatile acid, and on the application of a strong he.at, under ordinary atmosplieric pressure, it breaks up into several substances ; it may, however, be distilled under rediu'cd pressures, or in a current of superheated steam, when it passes over un- decomposed. If oleic acid be exposed to the action of nitrous acid, it is converted into another acid, termed claidic acid. The latter is a crystalline substance melting at about 40° C. (115° F. ) and having the same molecular composition as oleic acid. A very small quantity of nitrous acid is sufTieient to effect this remarkable change, the nature of which is unknown. 'hen heated with caustic potash, oleic acid breaks up into palmitic and acetic acids, as shown by the equation: C,.H„0, + 2K0H = Oleic acid Caiistii- potash C„,H„0,K 4- CJI,n,K -f Hj Palmitat*? of .fotntP of H.vdro- potas8ium potassium gen Oleic acid is a component of o/ci'/i (q.v.), which exists in most of the fats and fatty oils of the animal and vegetable kingdoms, and most abun- dantly in the liquid fats or oils, whence its name. It may be readily jnepaied in a pure state from fats rich in olein. For this purpose the fat employed is saponified by heating with a solution of caustic potash, and the soap thus obtained is decomposed with hydrochloric acid, which sets free the acids originally contained in the fat. The mixttire of acids is then treated with lead oxide at 100° C. (212° F.), and the oleate of lead is dissolved out of the mixture of lead salts obtained, by means of ether. On filter- ing and distilling off the ether, the oleate of lead is decomposed with hydrochloric acid, and the oleic acid is purified by cooling to about 6" or 7° below zero centigrade (about 20° F.), and re- moving the impurities, which remain liquid, by pressure and washing with small quantities of alcohol. With reference to the chemical constitution of oleic acid, it is known to contain a nornurl chain of eighteen carbon atoms and one double bond; but which two of the carbon atoms are linked to each other by that double bond has not yet been exactly asceitaincd. By the action of nascent hydrogen, oleic acid is readily converted into stearic acid ( q.v. ) . Of the oleales. or salts of oleic acid, the most important are the alkali salts, which are among the constituents of soap; they are soluble in water and in alcohol, and are precipitated from their aqueous solution by connuon salt. The lead salt, used as 'lead plaster' (diachylon plas- ter), may be obtained by adding lead acetate to an aqueous solution of sodium oleate; its formula is (C„H3,A)=Pb; it melts at 80° C. (170° F.). OLEIN, (Vle-in (from Lat. oleum, oil), or Tri- olein, CsHj ( CisHsaO™) 3. The glyceride of oleic acid. Pure olein is a colorless and inodorous oil, insoluble in water, and only slightly soluble in cold alcohol, but dissolves in ether in all propor- tions. By exposure to the air it darkens in color, becomes acid and rancid, and finally as- sumes a resinoid appearance. Nitrous acid con- verts it into an isomeric white solid fat named elaidin — the glyceride of elaidic acid. (See Oleic Acid.) Pure olein is obtained by cooling olive oil to 0° C. (32° F. ), which occasions tiie separation of the stearin and palmitin in a solid form. The fluid portion is then dissolved in alcohol, which on being cooled to 0° C, (32° F.) deposits in a solid form everything but olein, which is obtained in a pure state by driving off by heat the alcohol from the decanted or filtered solution. Olein is one of the three constituents common to all fats, the other constituents being palmitin and stearin. It forms the predominating con- stituent of liquid fats, such as olive oil and oil of almonds. See Fats; Oils; Glycerin; Oleic Acid. OL'ENEL'LUS (Xeo-Lat., diminutive of ole- nu.s) . An inqiorlant genus of trilobites charac- teristic of the Lower Cambrian series, for which reason these beds are termed the "Olcncllus zone.' The animal had a fiat, tapering body covered by a hard shell like that of a crab, made up of 14 loosely jointed segments, a broad head with large kidney-shaped eyes and long slender cheek.