Cementation

Cementation, a chemical process chiefly employed in the manufacture of steel and of porcelain glass. To convert wrought iron into steel, the bars are selected with care, broken into convenient lengths, and placed in layers in pots, mixed with and surrounded by charcoal. These pots are subjected to an intense heat, by which the carbon gradually penetrates the iron, and combines with it. Different views are entertained with regard to the formation of cement steel, but it is most probable that the carbonization of the iron bars, when heated in powdered coal with the exclusion of air, takes place by means of cyanogen compounds which are formed in the state of gas, rather than by a direct reaction of carbon or carbonic oxide gas. The American bank note company cement their engraved plates in carbon obtained from fine ivory turnings. Bottle glass is cemented with gypsum powder or sand, to form Reaumur's porcelain.

Ceneda

Ceneda, a town of Italy, in the province and 22 m. X. of Treviso; pop. about 8,000. It is the see of a bishop, and possesses a cathedral, several churches, manufactories of leather, woollens, and paper, and mineral springs.

Censer

Censer, a vessel for burning and wafting incense, used in the celebration of religious rites by the ancient Hebrews, Greeks, and Romans, and still retained in the Roman Catholic church. The Hebrew censer appears to have been a sort of chafing dish, with or without handles, which the high priest carried into the sanctuary or placed on the altar of incense. That used in the Catholic church, also called a thurible, is a vessel shaped much like a goblet, with a perforated lid, swung by long chains, and carried by an acolyte.

Censorinus

Censorinus, a Latin grammarian and chro-nologist of the 3d century, He wrote a treatise upon accents, cited by Cassiodorus, but lost. Only a fragment of his work De Metris is extant. He is known principally by a curious work entitled Be Die Natali, treating of the generation of man, his natal hour, the influence which the genii and stars exercise over his destiny, and of the climacteric periods of his life. He also discusses music, religious rites, and matters relating to astronomy, chronology, and cosmography. By this work the commencement of the era of Nabonassar and other dates have been fixed, and Censorinus has therefore been named by Scaliger eximius et doctissimus temporum vindex. The first edition of Censorinus is in quarto, without date, place, or printer's name; the second was that of Bologna, in 1497; the last is a German edition, by Gruber, in 1305.

Centairy

Centairy, a genus of plants of the family gentianacece, comprehending a large number of unimportant species, which are natives of Europe, Asia, Africa, and a very few of America. One of the species is fabled to have cured the centaur Chiron of the wound in his foot made by the arrow of Hercules, and to have hence derived its name. It was formerly supposed to have extraordinary medicinal powers, and said to cure not only fevers, but also the plague, and the worst ulcers; but its properties are only those of a bitter tonic, like those of other members of the same family.

Centaury.

Centaury.