EMPYEMA, a medical term signifying a diseased condition of the chest, in which pus accumulates in the pleura, cures of which are sometimes effected by drawing off the pus by means of tubes.

EMPYREAN, the highest heaven, or region of pure elemental fire, whence everything of the nature of fire has been conceived to emanate, whether in the phenomena of nature or the life of man.

EMS, 1, a river of NW.  Germany, rises in Westphalia, and after a course of 205 m. discharges into Dollart Bay, an inlet of the North Sea; is navigable, and is joined to the Lippe by means of a canal, and also similarly to Dortmund. 2, A celebrated German watering-place, on the Lahn, near Coblenz; its mineral springs, known to the Romans, vary in warmth from 80 deg. to 135 deg.  F.

ENAMEL, a vitreous compound, easily fusible, and coloured in various tints by the admixture of different metallic oxides; is fused to the surface of metals for utility and ornament; was known to the European and Asiatic ancients, and has maintained its popularity to the present day.  Various schools have been formed, of which the Byzantine, Rhenish, and Limoges are the most noted.

ENCAUSTIC PAINTING, an ancient style of decorative art somewhat similar to enamelling, which consisted in overlaying the surface (e. g. of walls) with wax, then inlaying a coloured design, the whole being subsequently polished.

ENCELADUS, one of the chief giants that revolted against Zeus, and who, as he fled and took refuge in Sicily, was transfixed by a thunderbolt, and buried under Etna.  The fiery eruptions of the mountain are his breath, and the shaking of it ascribed to his shifting from one side to another.  In the latter regard he serves in literature as the symbol of a blind, often impotent, struggle to throw off some oppressive incubus.

ENCELADUS, MANUEL BLANCO, a distinguished Chilian statesman and soldier, born in Buenos Ayres; trained for the navy in Spain, but joined the Chilian revolutionaries; served with distinction under Lord Cochrane, and rose to high rank both in the army and navy; was commander of the Chilian forces in 1825, and for two months in the following year President of the Republic; was subsequently Governor of Valparaiso, and minister to France (1790-1876).

ENCHIRIDION OF EPICTETUS.  See EPICTETUS.

ENCINA or ENZINA, JUAN DE LA, a Spanish dramatist, whose works mark the rise of the Spanish drama, born at Salamanca; was at one time secretary to the Duke of Alva, and afterwards conductor of music in the chapel of Leo X. at Rome (1469-1534).

ENCKE, JOHANN FRANZ, a celebrated German astronomer, born at Hamburg; determined the sun’s distance, and the orbit of the comet of 1680; calculated the time of the revolution of the comet which now bears his name, and which appeared in 1818; determined also the distance of the sun by the two transits of Venus in 1761 and 1769 (1791-1865).