Page:Collier's New Encyclopedia v. 09.djvu/359

LEFT TERNSTIICEMIACE^ 307 TERRAPIN TERNSTRCEMIACEiE, a natural order of polypetalous dicotyledonous plants, consisting of trees or shrubs, with alternate simple usually coriaceous leaves without stipules. The flowers are generally white, arranged in axillary or terminal peduncles, articulated at the base. This order is one of great eco- nomical importance, as it includes the genus Tliea, from which the teas of commerce are obtained. The favorite garden camellia also belongs to it. The plants belonging to the order are prin- cipally inhabitants of Asia and Amer- TERPENES, in chemistry, a term ap- plied to a series of hydrocarbons having the generic formula CnHzU — 4. They may be all classed under two heads, those produced by synthetical means, as valylene, C5H0, and carpene, C9H14; and those formed in plants, as the turpen- tines, C10H16. With the exception of the last, the terpenes have been very incom- pletely investigated. They are colorless or yellowish liquids, are insoluble in w^ater, but soluble in alcohol, ether, chlo- roform, benzine, and in the fixed and volatile oils. TERPILENE, an inactive hydrocar- bon, produced by the action of weak re- agents on the solid dihydrochloride, Cio Hia-2HC1. TERPINE, formula, C10H20O5H2O, a crystalline body, obtained by shaking for some time a mixture of eight parts oil of turpentine, two parts dilute nitric acid and one part alcohol. It forms large, brilliant, colorless, short, rhombic prisms, soluble in boiling water, alcohol, and ether, melts at 103°, and sublimes at a higher temperature in long needles. TERPINOL, formula, C2«Hr.40 ; a liquid of hyacinth-like odor, produced by heat- ing an aqueous solution of terpine with hydrochloric and sulphuric acids. It boils at 168°, and has a sp. gr. .852. TERPODION, in music, a keyed in- strument invented by John David Busch- mann, of Hamburg, about 1816, resem- bling a pianofoi'te in appearance, but pro- ducing notes from blocks of wood struck with hammers. The sound could be in- creased or diminished at pleasure. TERPSICHORE, in classical antiqui- ties, one of the muses, daughter of Jupi- ter and Mnemosyne. She presided over dancing, of which she was reckoned the inventress, and in which, as her name in- timates, she took delight. To her was sometimes ascribed the invention of the cithara, rather than to Mercury. She is represented as a young virgin crowned with laurel and holding in her hands a musical instrument. TERRACE, a raised level space or platform of earth, supported on one or more sides by masonry, a bank or plat- form of turf cr the like, such as may be seen in gardeiis, where they are used for ornament, cultivation, or promenade. In physical geography and geology, a platform, often of soft material, flat above and more or less steep on the sides. They often mark where the bed of the ocean or of a lake was succes- sively situated during the intervals be- tween elevatory movements. TERRA-COTTA, an Italian term for pottery or earthenware. The name is not ordinarily applied to pottery vessels with thin walls, but is confined to statues, statuettes, bas-reliefs, and architectural members such as columns, cornices, frie- zes, consoles, and the like made of burnt clay. But the term is not necessarily confined to articles of a decorative char- acter. The color of terra-cotta is either buff, yellow, or red, the former being the more common. Many masterpieces of ancient Greek and Roman sculpture are executed in this material, and a con- siderable number of works in burnt clay, by Italian artists who lived in the Mid- dle Age and early Renaissance periods, are also exquisite productions. Architec- tural ornaments of a very effective kind were also executed in this material in ancient times. Distinguished modern sculptors some- times produce works in terra-cotta, and in recent years it has been increasingly employed, either partly or wholly, for the fronts and other portions of impor- tant buildings. TERRA DI SIENNA, a ferruginous, ocherous earth, used as a pigment in both oil and water-color painting in its raw state and when burnt. In the lat- ter instance it becomes of a deep orange tint, and dries more rapidlv. It is trans- parent and durable; mixed with various blues, it yields many useful tints of green. TERRAPIN, the popular name of sev- eral species of fresh-water or tide-water tortoises forming the family EmydidsSt distinguished by a horny beak, a shield covered with epidermic plates, and feet partly webbed. They are active in their habits, swimming well and moving with greater agility on land than the land tortoises. They are natives of tropical and warmer temperate countries, many