Nickel-silver. German silver, or white metal, a compound of tin and nickel.
Niello. The art of chasing out lines or forms, and inlaying a black composition called nigellum or niello, was probably well known to the Greeks. The Byzantines compounded for this purpose silver, lead, sulphur, and copper, and laid it on the silver in a powder; being then passed through the furnace, it melted and incorporated with the solid metal. A process producing a similar result of black tracery is practised in porcelain painting, and called Niello-enamel.
Nigged Ashlar, O. E. Stone hewn with a pick or a pointed hammer, presenting a gnawed or nibbled surface: from the Swedish nagga, to gnaw.
Nilometer. A building erected, A. D. 847, in the island of Rhoda, opposite to Cairo, for recording the annual rise of the Nile (i. e. 16 cubits). It is a slender octagonal shaft about 20 feet in height, with a Corinthian capital. (See the Builder, xvii. 255.)
Nimbed, Her. Having the head encircled with a nimbus; usually represented by a circular line.
Nimbus (Lat. nimbus, a bright or black cloud). In Christian art, a disc or plate, commonly golden, sometimes red, blue, or green, or banded like a rainbow, placed vertically behind the heads of persons of special dignity or sanctity as a symbol of honour. After the 8th century living persons were, in Italy, distinguished by a square nimbus, which sometimes assumed the form of a scroll partly unrolled. The nimbus is of heathen origin. Virgil describes Juno as “nimbo succincta.” The heads of the statues of the gods, and the Roman emperors, after they began to claim divine honours, were decorated with a crown of rays. On medals of the Christian emperors also the nimbus is found, e.g. Constantine. In illuminated MSS. it is found on Pharaoh, Ahab, and other kings. It is a familiar symbol of dignity or power in the East, but does not appear as a Christian emblem before the 6th century. [See the article Nimbus in the Dict. of Christian Antiquities.] (See Aureole, Glory, Vesica Piscis, &c.)
Nincompoop, O. E. A corruption of the Latin non compos; a fool.
Ninth. In Music, an interval consisting of an octave and a tone, or semitone.
Nisan, Heb. The month in the Jewish calendar answering to our April.
Nitrate of Silver, used in photography, is silver dissolved in nitric acid.