OLEUM ARACHIS. 187 



vated very much the fruit Mani, a name still used for Arachis in Cuba 

 and in South America. A little later, Monardes/ described a nameless 

 subterraneous fruit, found about the river Maranon and held in great 

 esteemby both Indiansand Spaniards. But before, the French colonists sent 

 in 1555 by Admiral Coliguy to the Brazilian coast had become acquainted 

 with the " !Mandobi," which Jean de Lery- described quite unmistakably. 

 Good accounts and figures of it were given in the following century by 

 Johannes de Laet (1625),^ and by Marcgraf,* who calls it by its Brazilian 

 name of Mundubi. It is enumerated by Stisser among the rare plants 

 cultivated by him at Helmstedt (Brunswick), about the year 1697.' 



It is only in very recent times that the value of the Ground Nut 

 has been recognized in Europe. Jaubert, a French colonist at Goree near 

 Cape Verde, first suggested about 1840 its importation as an oil-seed 

 into Marseilles, where it now constitutes one of the most important 

 articles of trade.® 



Description — The fat oil of Ara^hiSySiS obtained by pressure without 

 heat, is almost colourless, of an agi'eeable faint odour and a bland taste 

 resembling that of olive oil. An inferior oil is obtained by warming 

 the seeds before pressing them. The best oil has a sp. gr. of about 

 0'918 ; it becomes turbid at 3° C, concretes at — 3° to — 4°, and hardens 

 at — 7°. On exposure to air it is but slowly altered, being one of the 

 non-drying oils. At length it thickens considerably, and assumes even 

 in closed vessels a disagreeable rancid smell and taste. 



Chemical Composition — The oil consists of the glycerides of four 

 different fatty acids. The common Oleic Acid, C^^H*^0-, that is to say 

 its glycerin compound, is the chief constituent of Arachis oil. Hypogceic 

 Acid, C^'^H^'^O", has been pointed out by Gossmann and Scheven (1854) 

 as a new acid, whereas it is thought by other chemists to agree with 

 one of the fatty acids obtained from whale oil. The melting point of 

 this acid from Arachis oil is 34-35° C. The third acid afforded by the 

 oil is ordinary Pcdmitic Acid, C^^H^'O^, with a fusing point of 62° C. 

 Arachic Acid, C"'^H**'0^ the fourth constituent, has also been met with 

 among the fatty acids of butter and olive oil, and, according to Oudemans 

 (1866), in the tallow of HepheliuTn lapjxiceiirii L., an Indian plant of 

 the order Sapindacece. 



When ground-nut oil is treated with hyponitric acid, which may be 

 most conveniently evolved by heating nitric acid with a little starch, a 

 solid mass is obtained, which yields by crystallization from alcohol 

 Elaidic and Gee id in ic acids, the former isomeric with oleic, the latter 

 with hypogreic acid. 



Production and Commerce — The pods are exported on an immense 

 and ever increasing scale from the West Coast of Africa. From this 

 region, not less than 66 millions of kilogrammes, value 26 millions of 

 francs (£1,040,000), were imported in 1867, almost exclusively^ into 



^ LasCosasquesetraendenuestras Indias ' Botanka curlosa, Helmst. 1697. 38. 



Occidentales, Sevilla, 1569, part 2. « Duval, Colonies et poliii'iue coloniale de 



- Histoire d'un voyage faict en la Terre du la France, 1864. 101 . — Mavidal, Le Senegal, 



Bresil, autrement dite Amerique, 1586. 204 sow ^ta< /^reVc?i<, soh aren/r, Paris, 1863.171, 



(first edition La Rochelle, 1578). — Carrere et HoUe, La Senigambie Fran- 



^Histo}reduiiouv€auMonde,lLeyde,lQ40. ^aise, 1855. 84. — Poiteau, in Annates des 



503. iiciences nat., Botanique, xix. (1853) 268. 



* Hist. Rerum Xat. Brasil. 1648. 37. 



