Encaustic Painting, a kind of painting practised by the ancients, for the perfecting of which heating or burning-in was required. Pliny distinguishes three species, in all of which wax was used with colours, and applied either with bronze instruments (cauteria), a sharp-pointed tool (cestrum), or brushes. The art has been revived in modern times, but has not been greatly employed. As the chief aim in encaustic painting was the securing of permanence and durability by the application of heat, the word encaustic has been applied to other and widely different processes. Thus it has been used for painting on earthen vessels, for painting on porcelain and work in enamel; and in the same way it
was given to the painting on glass of the Middle Ages.—Cf. A. P. Laurie, Greek and Roman Methods of Painting.
Encaustic Tiles, ornamental paving-tiles of baked pottery, much used during the Middle Ages in the pavements of churches and other ecclesiastical buildings. The encaustic tile, strictly so-called, was decorated with patterns formed by different coloured clays inlaid in the tile and fired with it. The art appears to have originated in the latter part of the twelfth century, to have attained its highest perfection during the thirteenth, and to have sunk into disuse in the fifteenth. During the whole of this period it was principally carried on in England and Normandy. After a long lapse the art was revived in England in 1830 by Wright, a Shelton potter. In modern manufacture two methods are employed, the 'plastic' and the 'semi-dry' or 'dust' method. The first is, in all essentials, that used in the Middle Ages, except, perhaps, in the perfection of modern moulding appliances; the second consists in ramming pulverized clay with a minimum of moisture into metal dies, the subsequent firing of tiles thus consolidated being attended with less risk from shrinkage.
Ence´nia, festivals anciently commemorative of the founding of a city or the dedication of a church; and in later times periodical ceremonies, as at Oxford, in commemoration of founders and benefactors.
Encephalartos, a genus of Cyeads, natives of Africa. Meal (Kaffir-bread) is made from the pith by the natives.
Enchanter's Nightshade, a name common to plants of the genus Circæa, nat. ord. Onagraceæ, of which there are two British species, C. lutetiāna and C. alpīna. The former is about a foot and a half high, and has delicate ovate leaves, small white flowers tinged with pink, and small roundish fruits covered with hooked bristles. It abounds in shady woods. C. alpīna, which is similar, but smaller and more delicate, is found in Scotland and north of England. They have no affinity with the nightshades.
Enchorial (en-kō´ri-al) Writing, the form of writing used by the old Egyptians for the common purposes of life, as distinct from the hieroglyphic and hieratic (used by the priests). It is also called Demotic.
Encke (en´ke), Johann Franz, German astronomer, born at Hamburg in 1791, died in 1865. He studied under the astronomer Gauss at Göttingen. During the War of Liberation (1813-5) he served as artillerist in the German army, and after the peace became assistant in the observatory of Seeberg, near Gotha. Here he calculated the orbit of the comet observed by Mechain, Miss Herschel, and Pons, predicted its return, and detected a gradual acceleration of movement, ascribed by him to the presence of a resisting medium. The comet is now known as Encke's comet. The fame of his works Die Entfernung der Sonne (The Distance of the Sun) and Der Venusdurchgang von 1769 (Transit of Venus of 1769) led to his appointment as director of the Berlin Observatory (1825), a position which he held till his death. From 1830 he edited the Berliner Astronomisches Jahrbuch.
Encke's Comet. This object was seen in 1786, and at some subsequent returns, before it was discovered by Encke in 1819 to be a periodic comet. It has since been observed at numerous returns. It revolves round the sun in about three and one-third years, having the shortest period of any comet known. It has exhibited very prominently the feature, shown by many comets, of a contraction of the head or coma on approaching the sun. Encke's comet long manifested the most remarkable feature of a shortening of its period by about two and a half hours in each revolution. The suggestion was made that this was due to resistance by a rare medium generally diffused in the solar system, which had the effect of reducing its aphelion distance and diminishing its orbit. This, however, is improbable, as other comets show no similar effect. The cause remains undiscovered, and a further extraordinary fact is that the shortening of period is found since 1868 to have been only half of its previous amount.
Enclave (a˙n-klāv), a term used in German and French to denote a place or country which is entirely surrounded by the territories of another power.