Page:Encyclopædia Britannica, Ninth Edition, v. 7.djvu/185

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nearly the form and size given by Tavernier, and the Koh-i-noor would then surpass all known diamonds in its magnitude as in its eventful history.

It is not necessary to notice in detail other diamonds of smaller size, as the Saucy, of 53/ carats, once the property of Charles the Bold, like the Austrian, and afterwards of Louis XIV. of France, but sold in 1830 for 20,000 to the emperor of Russia. In the Russian treasury are also the Shah of 86 carats, and the Polar Star of 40. Other noted ones are the Nassac of 89f carats (now recut, and 78

Perhaps even more important is the use of the diamond for cutting glass, for polishing gems and other hard bodies, and recently by engineers for boring machines used in form ing tunnels and artesian wells. The glaziers diamond is about the size of a pin s head, and is set in copper or brass. The curvature of the fracture faces gives a sharp edge that cuts and not scratches merely. Each costs about 12s. to 18s., and, as it will weigh only about ^th carat, the price B higher than that used as gems. For polishing purposes the so-called " bort," i.e. stones so imperfect in form and quality as to be useless for ornament, are broken down and crushed into diamond powder. The carbonado from Bahia is also employed both for polishing and for boring machines. In the latter the stones are fixed in a ring of steel, made to revolve with great rapidity, and kept cool by a current of water, which also removes the detritus In consequence its price has risen lately from about Is. to 18s. or 20s. a carat.


The literature of the diamond is very extensive, and scattered through many works. Its history in ancient times is given by Finder, l)c Adamante, Berlin, 1829 ; its general character in treatises on mineralogy and on precious stones—of the latter those by Jeffries, London, 1757 ; Mawe, ib. 1831 ; Emanuel, ib. 1865 ; and Streeter, ib. 1877 ; with the EdeMeinkundc of Kluge, Leipsic, 1860, and of Schrauf, Vienna, 1869, may be mentioned. More special are Murray, Memoir on the Diamond, London, 1831 ; Petzholdt, Be.itra.ge zur Natur d. Diamanten, Dresden, 1842 ; Goeppert, Ueber Einschliisse in I)., Haarlem, 1864 ; and many papers in the journals and transactions of scientific societies. For its mode of occurrence may be consulted : in India, Heync s Tracts, London, 1814; Hitter s Erdkiuide, Asien, vol. iv. ; and many papers by Voysey, Adam, Franklin, Blandford, and others ; in Brazil, Mawe s Travels, London, 1812 ; Eschwege, Claussen, Spix and Martius, Gardner, Tschudi, &c. ; for the Ural, Eose s JRcise, vol.. i., but with much general information ; for Australia, Liversidge, in Jour. Geol. Society ; for the Cape, many papers in the Journals of Geol. Society and the Society of Arts, and in the Geological Magazine, by R. Jones, Tennant, Dunn, Maskelyne, Flight, and Stow ; and by Cohen in Leonhard and Gemetz s Jahrbuch.

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DIANA, who was at a later period reverenced as the Greek Artemis by the side of Apollo, was originally an independent deity of Italy, as, indeed, is shown by the name, which is the feminine form of Janus. She is essentially the moon goddess, and presides over wood, plain, and water, as well as over the changes of human character, and the special functions of the female sex, also over chase and war. Diana was worshipped by the Sabiues, but more especially by the ^Equi, Heruici, and Latins, whose united sanctuary lay in the wooded hills of Algidus beyond Tusculum. Diana had also a sanctuary in Anagnia, the capital of the Hernici, and another in Corne, near Tusculum. But more celebrated than all these was the grove and sanctuary of Diana of Aricia, on the Lake of Nemi, which gave the name of Nemorensis to Diana. Here she was worshipped side by side with a male deity Virbius. After the destruction of Alba Longa this grove was for a long time the united sanctuary of the neighbour ing Latin and Rutulian cities, until at last it was extin guished beneath the supremacy of Rome. The festival of the goddess was on the ides of August, the full moon of the hot season. She was worshipped with torches, her aid was sought by women seeki&g a happy deliverance in childbirth, and many votive offerings have rewarded modern excava tions on the site. Another celebrated sanctuary of Diana was that on the slopes of Mount Tifata, near Capua, where she was worshipped under the name of Tifatina. This sanctuary was specially favoured by Sulla and at a later period by Vespasian. There were several ancient groves and sanctuaries of Diana in Rome, one in the Vicus Patricius between the Vimiual and Esquiline, into which no man was admitted, another at the highest point of the Vicus Cyprius, another on the Coeliolus. But the most celebrated of all was the temple on the Aventiiie. This was originally a sanctuary of the Latin League, which accounts for the hill not being included in the original circuit of Rome, and for its being the refuge of the plebeians in political disturbances. The statue of the goddess was of the Ephesian type, the day of dedication was the ides of August, and the temple was especially fre quented by slaves and their wives. Runaway slaves throughout Italy had a special dependence upon Diana. Such are the chief characteristics of the Roman Diana ; but as early as 400 B.C. she began to be identified with the Greek Artemis, of which an account has already been given (see Artemis). For fuller information see Preller, 11 6 m isch e Mytholog ie.

DIANO, or Teggiano, a town of Italy in the province of Principato Citeriore, 45 miles south-east of Salerno, on an isolated eminence, above the upper part of the valley of the Negro, or Tanager, to which it gives the name of Val di Diano. It represents the ancient Tegianum, a municipal town of Lucania, of which the ruins -can still be traced at the foot of the hill ; and it possesses a castle, several churches of some interest, and three conventual buildings. In 1497 it was strong enough to resist, under Antonio Sanseverino of Salerno, the siege undertaken by Frederick of Aragon. Population in 1871, 6224.

DIAPHORETICS (from Sia<j>o P , to carry through), such remedies as promote perspiration. In health there is constantly taking place an exhalation of watery vapour from the skin, by which not only are many of the effete products of nutrition eliminated, but the body is kept cool. Under exertion or in a heated atmosphere this natural function of the skin is increased, sweating more or less profuse follows, and, evaporation going on rapidly over the whole surface, little or no rise in the temperature of the body takes place. In many forms of disease, such as fevers and inflammatory affections, the action of the skin is arrested, and the surface of the body feels harsh and dry, while the temperature is greatly elevated. The occurrence of perspiration not unfrequently marks a crisis in such diseases, and is in general regarded as a favourable event. In some chronic diseases, such as diabetes and some cases of Bright s disease, the absence of perspiration is a marked feature ; while, on the other hand, in many wasting diseases, such as phthisis, the action of the skin is increased, and copious exhausting sweating occurs. Many means can be used to induce perspiration, among the best known being baths, either in the form of hot vapour or hot water baths, or in that part of the process of the Turkish bath which consists in exposing the body to a dry and hot atmosphere. Such measures, particularly if followed by the drinking of hot liquids and the wrapping of the body in warm clothing, seldom fail to excite copious perspiration. Numerous medicinal substances have a similar effect, although the modus operandi