Page:Encyclopædia Britannica, Ninth Edition, v. 5.djvu/212

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centuries one of thsmost splendid sights of Rome. In the time of Dionysius the cavalcade consisted of 5000 horsemen,

all persons of fair repute and independent fortune.

CASTOR OIL, the fixed oil obtained from the Castor Oil Plant or Palma Christi, Kicinus communis, belonging to the Natural Order Euphorbiacece. The plant is a native of the East Indies, but it has been introduced, and is now cultivated in most tropical and in the wanner temperate countries. In size it varies from a shrubby plant to a tree of from 30 to 40 feet in height according to the climate in which it grows, being arborescent in tropical latitudes. On account of its very large beautiful palmate-peltate leaves, which measure as much as 2 feet in diameter, it is cultivated as an ornamental plant. In the south of England, with the habit of an annual, it ripens its seeds in favourable seasons ; and it has been known to come to maturity as far north as Christiania in Norway. The fruit consists of a tricoccous capsule, covered externally with soft yielding prickles, and each cell develops a single seed. The seeds of the different cultivated varieties, of which there are a great number, differ much in size and in external markings ; but average seeds are of an oval laterally compressed form, with their longest diameter about four lines. They have a shining, marble grey and brown, thick, leathery epidermis, within which is a thin dark-coloured brittle coat. The cotyledons readily separate, and show a large distinct leafy embryo. The oil is obtained from the seeds by two principal methods expression and decoction, the latter process being largely used in India, where the oil, on account of its cheapness and abundance, is extensively employed for illuminating as well as for other domestic and medicinal purposes. The oil exported from Calcutta to Europe, which is said to be " cold drawn and nearly tasteless," is prepared by shelling and crushing the seeds between rollers. The crushed mass is then placed in hempen cloths and pressed in a screw or hydraulic press. The oil which exudes is mixed with water and heated till the water boils, and the mucilaginous matter in the oil separates as a scum. It is next strained, then bleached in the sunlight, and stored for exportation. A considerable quantity of castor oil of an excellent quality is also made in Italy ; and in California the manufacture is conducted on an extensive scale. The following is an outline of the process adopted in a Californian factory. The seeds are submitted to a dry heat in a furnace for an hour or thereby, by which they are softened and prepared to part easily with their oil. They are then pressed in a large powerful screw- press, and the oily matter which flows out is caught, mixed with an equal proportion of water, and boiled to purify it from mucilaginous and albuminous matter. After boiling about an hour, it is allowed to cool, the water is drawn off, and the oil is transferred to zinc tanks or clarifiers capable of holding from 60 to 100 gallons. In these it stands about eight hours, bleaching in the sun, after which it is ready for storing. By this method 100 Ib of good seeds yield about 5 gallons of pure oil.

Castor oil is a viscid liquid, almost colourless when pure, possessing only a slight odour, and a mild yet highly nauseous and disagreeable taste. Its specific gravity is 96, a little less than that of water, and it dissolves freely in alcohol, ether, and glacial acetic acid. It contains palmitic and several other fatty acids, among which there is one ricinoleic acid peculiar to itself. In 1864 Tuson isolated from the oil a principle which he denominated an alkaloid under the name of ricinine, and that substance has since been extracted from the leaves, which are used as galactagogues and emmenagogues. Castor oil forms a clean, light-coloured soap which dries and hardens well, having no tendency to deliquesence, and is free from smell. It has been recommended for medicinal use.

Castor oil is one of the most extensively useful of purgative medicines known ; and the only one which, under certain circumstances, can with safety be administered. Its purgative properties were supposed by Soubeiran to be due to the presence of an acrid oleo-resin and to ricinolein, but the constituents of the oil have not yet been satisfactorily studied in their physiological relations. The seeds themselves, or the oil extracted by alcohol, owing to the larger proportion of the drastic principle they contain, act much more powerfully than the common oil. The nauseous taste of castor oil is the one great impediment to its use, and many methods have been suggested for overcom ing its unpleasant flavour. The most common devices are enclosing it in capsules, floating it in various palatable liquids, or preparing emulsions of the oil with such sub stances as dissolved gum-arabic and simple syrup.

CASTREN, Matthias Alexander (1813-1853), one

of the greatest authorities on the ethnology and languages of the Northern Asiatic nations, was born at Tervola, in the parish of Kemi in Finland, on 20th November (2d December) 1813. His father, Christian Castren, parish minister at Rovaniemi, died in 1825 ; and Matthias passed under the protection of his uncle, Mathias Castren, the kindly and learned incumbent of Kemi. At the age of twelve he was sent to school at Uleaborg, and there ho helped to maintain himself by teaching the younger children. On his removal to the Alexander s University at Helsingfors in 1830, he first devoted himself to Greek and Hebrew with the intention of entering the church ; but his interest was soon excited by the language of his native country, and he even began before his course was com pleted to lay the foundations of a work on Finnish mythology. The necessity of personal explorations among the still unwritten languages of cognate tribes soon made itself evident ; and in 1838 he was glad to join a medical fellow-student, Dr Ehrstrom, in a journey through Lapland. In the following year he travelled in Russian Karelia at the expense of the Literary Society of Finland ; and in 1841 he undertook, in company with Dr Elias Lonnrot, the great Finnish philologist, a third journey, which ultimately extended beyond the Ural as far as Obdorsk, and occupied a period of three years. Before starting on this last expedition he had published a translation into Swedish of the Finnish epic of Kalevala ; and on his return he gave to the world his Elementa grammatices Syrjaence and Ele- menta grammatices Tscheremissce , 1844. No sooner had he recovered from the illness which his last journey had occasioned than he set out, under the auspices of the Academy of St Petersburg and the Helsingfors University, on an exploration of the whole government of Siberia, which resulted in a vast addition to previous knowledge, but seriously affected the health of the adventurous investi gator. The first-fruits of his collections were published at St Petersburg in 1849 in the form of a Versuch einer Ostjakischen Sprachlehre. In 1850 he published a treatise De affixis personalibus linguarum Altaicarum, and was appointed professor at Helsingfors of the new chair of Finnish language and literature. The following year saw him raised to the rank of chancellor of the university ; and he was busily engaged in what he regarded as his principal work, a Samoyedic Grammar, when he died on 7th May 1853. Five volumes of his collected works appeared from 1852 to 1858, containing respectively (1.) Reseminnen frdn dren 1838-1844 ; (2.) Reseberaitelser och bref dren J 845-1 849 ; (3.) Foreldsningar i Finsk myth-ologi ; (4.) Ethnologiska fureldsningar cfver Altaiska folken; and (5.) Smdrre afhandlingar och akademiska dissertationer. A German translation has been published by Anton Schiefner, who was also intrusted by the St

Petersburg Academy with the editing of his manuscripts