Chapter M (2)

=Muffs= were introduced into England from France in the reign of Charles II. They were previously known in England, but were subsequently more common, and used by both sexes. Very little variation has occurred in their manufacture.

=Muglias=, Arab. A kind of pastilles; a substance employed in the Middle Ages for making odoriferous beads; they were burnt for fumigations.

=Mulctra=, =Mulctrale=, =Mulctrum=, R. and Chr. (_mulgeo_, to milk). A milk-pail for milking cows. In Christian archæology it is a pastoral vessel which is a eucharistic symbol.

=Mullets=, Her. Stars generally of five, but sometimes of six or more rays. Fig. 470 is of the date 1295, and Fig. 471 its development in 1431.

=Mulleus=, =Mule=, R. (_mullus_, a red mullet). A red half-boot, which only certain magistrates had the right of wearing, viz. the ancient dictators, consuls, prætors, censors, and ædiles.

=Mullions= or =Munnions=, Arch. The slender piers which separate a window into several compartments.

=Multifoiled=, Arch. Having many FOILS (q.v.). This term is synonymous with POLYFOILED.

=Mummy.= This pigment _should_ be made of the pure Egyptian asphaltum, ground up with drying oil or with amber varnish.

=Mummy-cloths= (=Egyptian=) were of fine unmixed flaxen linen, beautifully woven, of yarns of nearly 100 hanks in the pound, with 140 threads in an inch in the warp, and about 64 in the woof.

=Muniment-rooms=, to be strong and fire-proof, were erected over porches, gateways, &c. They contained charters, archives, &c. (See CHARTER-HOUSE.)

=Munnions=, Arch., for MULLIONS (q.v.).

=Mural.= Generally, on a wall; as—

=Mural Arch.= An arch against a wall, frequent in the aisles of mediæval buildings.

=Mural Crown= (Her.) represents masonry, and is embattled. (See CORONA.)

=Mural Monument.= A tablet fixed to a wall, &c.

=Mural Painting.= (See FRESCO, TEMPERA, &c.)

=Murex=, R. (1) A Triton’s horn or conch; (2) _murex ferreus_, a caltrap, thrown down to hinder the advance of cavalry, its long spikes being so arranged as to pierce into the horses’ feet, and so disable them. (See CALTRAPS.)

=Murrey=, O. E. A reddish purple or mulberry colour. The livery of the House of York.

=Murrhina=, =Murrhea=, and =Myrrhina=, R. Murrhine vases; they are spoken of by Pliny, and have given rise to interminable treatises and discussions, with the sole result that no light whatever has been thrown on the nature of these vases.

=Murrhine Glass.= (See GLASS.)

=Murus=, R. Walls as defences and fortifications, in contradistinction to _paries_, the wall of a building. Fig. 473 represents a portion of the walls of Megalopolis. (See MŒNIA.)

=Muscarium=, R. (_musca_, a fly). (1) A fly-flap. Hence (2) The tail of a horse. (3) A case in which papers were shut up in order to preserve them from fly-stains.

=Muses=, the personifications of the liberal arts, are represented conventionally as follows:—

Calliope. The Muse of epic poetry; a tablet and stylus, sometimes a roll.

Cleio. The Muse of history; seated in an arm-chair with an open roll of paper, sometimes with a sun-dial.

Euterpe. The Muse of lyric poetry; with a double flute.

Melpomene. The Muse of tragedy; with a tragic mask, the club of Hercules, and sword; crowned with the vine-leaves of Bacchus, and shod in the _cothurnus_; often heroically posed with one foot on a fragment of rock.

Terpsichore. The Muse of choral dance and religious song; with lyra and _plectrum_. As the Muse of religious poetry, her expression is dignified and earnest.

Erato. The Muse of erotic poetry and soft Lydian music; sometimes has the lyre, sometimes is represented dancing, always gentle and _feminine_ in expression.

Polyhymnia. The Muse of the sublime hymn and divine tradition; usually appears without any attribute, in an attitude of meditation; sometimes the inscription ΜΥΘΟΥΣ (_of the myth_).

Urania. The Muse of astronomy; points with a staff to a celestial globe. (Lachesis, one of the Parcæ, has the same attributes.)

Thaleia. The Muse of pastoral life, of comedy, and of idyllic poetry; appears with the comic mask, a shepherd’s staff, and a wreath of ivy, or basket; sometimes dressed in a sheepskin.

The Muses are sometimes represented with feathers on their heads, alluding to their contest with the Sirens, whom they stripped of their wing feathers, which they wore as ornaments. (_Hirt. Mythologisches Bilderbuch_, p. 203.)

=Museum=, Gr. and R. (Μουσεῖον). Literally, a temple of the Muses. The term was afterwards applied to an establishment founded by Ptolemy I., called Soter, at Alexandria in Egypt, in which scholars and literary men were maintained at the public expense. In a villa, it was a grotto or retreat to which people retired for meditation.

=Musivum= (opus), R. (μουσεῖον). This term was used by the Romans to denote a mosaic of small cubes of coloured glass or enamel, in contradistinction to LITHOSTROTUM (q.v.), which was a pavement made of real stones and marbles of different colours; but in a more extended sense, the term Musivum denotes any kind of mosaic. Figs. 474 and 475 show examples of various kinds. Fig. 476 is a mosaic forming a border.

=Muslin=, originally esteemed for the beauty with which gold was woven in its warp, took its name from the city of Mousull in Turkey in Asia.

=Musquet.= A long heavy match-lock gun, introduced from Spain in the Dutch wars of the 16th century, which eventually displaced the harquebus. (See SNAPHAUNCE and WHEEL-LOCK.)

=Musquet-rest.= A staff with a forked head required to support the musquet. It was trailed by a string from the wrist.

=Mustarde Villars=, O. E. Either (1) a kind of cloth, probably so named from Moustier de Villiers, near Harfleur; or else (2) (as Stowe says) “a colour, now out of use.” _Mustard_ was a favourite colour for liveries and official dresses in the 15th century.

=Mutatio=, R. Literally, _change_. The Romans gave the name of _mutationes_ to the posthouses for relays of horses established along the high roads for the service of the state.

=Mutch=, O. E. An old woman’s close cap. (_Fairholt_.)

=Mute=, Fr. This term, derived from the Latin _muta_, is employed by ancient authors as a synonym for _belfry_, _turret_, or _bell-tower_.

=Mutule=, Arch. In a general sense, any stone or wooden projection which stands out beyond the surface of a wall, such as a rafter, for instance. In a more restricted sense, it denotes an architectural ornament characteristic of the Doric order, consisting of a square block placed at equal intervals above the triglyphs and metopes in a Doric cornice. In the Corinthian order _mutules_ are replaced by modillions.

=Mynchery=, A.S. A nunnery. The word survives in local dialects, and is applied to the ruins; e. g. of the ancient _mynchery_ at Littlemore, near Oxford.

=Myrtle Crown= for bloodless victors. The _myrtle_ was sacred to Venus. It flourished on the sea-coast of Italy and Greece. The wood is very hard, and is used for furniture, marquetry, and turning. Another myrtle wood from Van Diemen’s Land is beautifully veined for cabinet-work.

=Myth=, Gen. (μῦθος, lit. that which is spoken). The name given to obscure traditions handed down from remote antiquity, antecedent to written or precise history; opposed to _legendary_ record (which can be _read_).

N.

=Nablia=, =Nablum=. A stringed musical instrument; a kind of _cithara_ in the shape of a semicircle.

=Nacre=, Fr. Mother-of-pearl, the iridescent inner lining of the pearl mussel or oyster.

=Nacreous Shells.= Iridescent shells. Several kinds are used for manufactures, as some species of _Meleagrina_, _Turbo_, _Nautili_, &c.

=Nadir= (Arab. _nadhir_, opposite). The part of the heavens directly under our feet; opposite to the ZENITH.

=Nænia.= (See NENIA.)

=Naga=, Malay. Jars with the figure of a dragon traced on them.

=Naga Architecture= (Hind. _naga_, a poisonous snake). Temples dedicated to the worship of the seven-headed snakes are found in Cashmere, remarkable for their identity of style with the Grecian Doric, unlike anything found in any other part of India. [Consult _Fergusson_, _History of Architecture_, ii. 703–732.]

=Nagara.= A Hindoo name for a music-gallery in front of the Jain temples.

=Nahinna.= A Persian manufacture of majolica. The Comte de Rochechouart says that the ancient faience of Persia is as admirable as the modern is detestable, though it retains a degree of oriental elegance.

=Naiad.= A water-nymph.

=Nail.= In cloth measure, 2¼ inches.

=Nail-head Moulding=, Arch. An ornament formed by a series of projections resembling round or angular _nail-heads_.

=Nainsook=, Hind. A thick sort of jaconet muslin.

=Naipes=, Sp. Playing-cards. The word is supposed to be derived from the initials of Nicolao Pepin, the inventor. (_Diccionario de la Lengua Castellana._) Hence the Italian _naibi_.

=Naked Flooring=, Arch. The timber-work which supports a floor.

=Namby-pamby.= Affectedly pretty. The term originated in criticism of an English poet of the 17th century—Ambrose Phillips.

=Nancy Biscuit.= A peculiar porcelain made at Nancy. The faïencerie was established in 1774 by Nicolas Lelong.

=Nankeen.= A buff-coloured cotton cloth, introduced from the province of Nankin, in China.

=Nân-mo=, Chinese. A beautiful wood, resembling cedar, used for temples, palaces, and houses of state.

=Nantes.= Manufactories of white faience were established here in 1588 and 1625; and that of Le Roy de Montilliée and others in the 18th century.

=Naology.= The science of temples. (See _Dudley’s Naology, or a Treatise on the Origin, Progress, and Symbolical Import of the Sacred Structures of the World_.)

=Naos=, Gr. The interior apartment of a Greek temple; the _cella_ of the Roman temple.

=Napery.= A general term for made-up linen cloth.

=Naphthar=, Heb. (lit. _thick water_). The name given by Nehemiah to the substance that they found in the pit where the sacred fire of the temple had been hidden during the Captivity. This “thick water, which” (the legend says) “being poured over the sacrifice and the wood, was kindled by the great heat of the sun and then burnt with an exceedingly bright and clear flame,” was the naphtha of modern commerce.

=Napiform= (Lat. _napus_, a turnip). Turnip-shaped.

=Napkin= (little _nape_). A pocket-handkerchief.

“Your napkin is too little.” (_Othello._)

=Napkin Pattern.= A decorative ornament very common in German wood-carving of the 15th and 16th centuries. (See LINEN-SCROLL.)

=Naples Majolicas= were already celebrated early in the 16th century. M. Jacquemart describes some vases of colossal size, evidently constructed for “la grande décoration,” being painted on only one face; handles in the form of caryatids add to the majestic appearance of these vases; the subjects are scriptural, executed in blue camayeu picked out in black; the design is free, elegant though rather straggling, and the touch is bold and spirited.

=Naples Yellow= (It. _giallolino_). A compound of the oxides of lead and antimony, having a rich, opaque, golden hue. As a pigment for oil painting and for porcelain and enamel, it is now superseded by chromate of lead. As a water-colour pigment it is liable to blacken upon exposure to damp or bad air.

=Napron.= An apron used by mediæval masons. _Limas_ was another kind of apron worn by them.

=Nard= (Lat. _nardus_). Ointment prepared from the spikenard shrub.

=Nares=, Lat. (the nostrils). (1) The perforations in the register-table of an organ, which admit air to the openings of the pipes. (2) The issue of a conduit.

=Nargilé= or =Narghilly=, Persian. A tobacco-pipe with an arrangement for passing the smoke through water. The illustration is the bowl of a Persian pipe of this description, in Chinese porcelain. (Fig. 477.)

=Nariform= (Lat. _naris_, the nostril). Nose-shaped.

=Narthex=, Chr. The vestibule of a church; sometimes within the church, sometimes without, but always further from the altar than the part where the “faithful” were assembled. Hence it was a place for the catechumens. The narthex communicated with the _nave_ by the “beautiful gates,” and with the outside by the “great gates.” In monastic churches the narthex was the place for the general public.

=Nasal=, O. E. The bar of a helmet which protected the nose.

=Nask=, Hind. A _quoin_, or coin-stone.

=Natalitii Ludi=, R. Games in the circus in honour of an emperor’s birthday.

=Natatorium.= A cold swimming-pool in the baths. That at Pompeii is of white marble twelve feet ten inches in diameter, and about three feet deep, with three marble steps, and a seat round it raised about ten inches from the bottom. There is a platform or _ambulatory_ round the bath, also of marble. (See SIGMA.) The ceiling is vaulted, with a window in the centre. (See BAPTISTERIUM.)

=Natatorium=, Chr. A baptismal font; Gr. κολυμβήθρα (_piscina probata_).

=Natinz.= A Persian manufacture of majolica. (See NAHINNA.)

=Nativity.= While the Adoration of the Magi is one of the commonest subjects of early Christian art, the Nativity is one of the rarest. It is not found in any catacomb frescoes, or the mosaics of any basilicas or churches. The only examples are sculptural, and this on ivories, gems, &c. On these generally the Child is seen wrapped in swaddling clothes as the central object, the star appears above, the Virgin on a rude couch, and sometimes St. Joseph rapt in thought, his head resting on his hand; the ox and the ass appear behind, and shepherds with curved staves stand by adoring.

=Natural.= In Music, a character marked ♮ used to correct the power of a previous _sharp_ or _flat_. A _natural scale_ is a scale written without sharps or flats.

=Naturalisti=, It. Artists who work on the principle of a close adherence to the forms and colours actually combined in natural objects. The epithet was particularly applied as a term of reproach to the founders of the modern Dutch school of painting. (See IDEAL.)

=Naumachia= (ναῦς, a ship, and μάχη, a battle). (1) A spectacle representing a sea-fight, a subject frequently represented on coins and sculptures. (2) A building erected for such shows. Napoleon I. had a theatre at Milan filled with water for a sea-fight.

=Nautilus.= A shell-fish that sails on the surface of the sea in its shell. Its spiral univalve shell is a common motive in ornamental design.

“Learn of the little nautilus to sail,
Spread the thin oar, and catch the driving gale.”
(_Pope._)

The illustration is the device of the Affidati, an Italian literary Academy, with the motto “Safe above and below.”

=Navalis Corona.= (See CORONA NAVALIS.) (Fig. 480.)

=Nave=, Arch. (so called from its vaulted roof resembling in shape an inverted ship (_navis_); or from _nave_, the centre of anything). The middle part or body of a church between the aisles, extending from the _choir_ to the principal entrance. The Germans call this part of a church “Schiff.”

=Navette=, =Navicula=, Chr. The vessel, in the shape of a boat, in which incense is placed for the supply of the thurible.

=Navicella=, Chr. A celebrated mosaic, at Rome, of a ship tossed by storms and assailed by demons; emblematic of the Church.

=Neanderthal.= A valley near Dusseldorf, in which bones and skulls were found of men asserted to have been _præadamite_.

=Neat-house=, O. E. A cattle-shed.

=Nebris=, Gr. (from νεβρὸς, a fawn). A fawn’s skin, worn originally by hunters; an attribute of Dionysus, and assumed by his votaries. It is represented in ancient art as worn not only by male and female _bacchanals_, but also by Pans and Satyrs. It was commonly put on in the same manner as the _ægis_, or goat’s skin, by tying the two fore-legs over the right shoulder, so as to allow the body of the skin to cover the left side of the wearer.

=Nebular= (Lat. _nebula_, a mist). Belonging to the nebulæ, or clusters of stars only visible as a light, gauzy appearance or mist in the skies.

=Nebule Moulding.= A decorated moulding of Norman architecture, so called from the edge forming an undulating or waving line. (See Fig. 481.)

=Nebulée=, Her. A dividing and border line, as represented in Fig. 482.

=Nebulous.= Cloudy or hazy.

=Nebuly=, Her. Ornamented with light wavy lines.

=Neck=, Arch. The plain part at the bottom of a Roman Doric or other capital, between the mouldings and the top of the shaft. (See HYPOTRACHELIUM.)

=Necklaces.= An ornament common to all ages and nations. The ancient EGYPTIANS of both sexes wore them of gold or beads, generally with a large drop or figure in the centre, and strung of the various religious emblems; amethysts, pearls, gold or cornelian bottles, imitations of fish, shell, and leaves; finally, an infinite variety of devices. (See _Wilkinson’s Ancient Egyptians_, ii. 343.) An illustration of a common form of GREEK necklaces is given under _Crotalium_. The BRITISH women of the earliest ages wore necklaces of jet, ivory, and amber, beads, shells, &c., besides gold links hooked together. (See also MONILE, TORQUE.) The Anglo-Norman ladies do not appear to have worn necklaces, and no mediæval examples are found earlier than the 15th century. (See Figs. 303, 304, 483.)

=Neck-mouldings=, Arch. The mouldings at the bottom of the capital, in Gothic architecture.

=Necrodeipnon=, Gr. A feast after a funeral; a common subject on tombs. A horse’s head is usually placed in one corner of the representation, as an emblem of death as a journey.

=Necrologium=, Chr. A book kept in religious houses for the names of the founders and benefactors to be mentioned in the prayers.

=Necromancy= (Gr. νεκρὸς, the dead, and μαντεία, prophecy). Calling up the spirits of the dead for divination; hence generally applied to conjuring. Necromancy was practised in two ways: by inspection of the entrails, and by invoking the dead.

=Necropolis=, Gr. A city of the dead; a cemetery.

=Nectar=, Gr. The drink of the gods.

=Necysia=, Gr. Offerings of garlands of flowers and other objects made at the tombs of deceased relatives on the anniversary of the day of death, or, as some suppose, on their birthdays. (See GENESIA.)

=Needfire=, or Fire of St. John Baptist (Old Germ. _Nodfyr, Niedfyr_). A superstitious practice of the ancients, derived from a pagan source, of celebrating the birthday of St. John Baptist at the midsummer solstice (St. John’s Eve) by lighting fires, carrying about firebrands, or rolling a burning wheel. The practice is one of many examples of the caution with which the evangelizing ecclesiastics of the Middle Ages refrained from abruptly disturbing the deeply-rooted superstitions of the ancient Germans. [Consult _Grimm’s German Mythology_; _Brand_, _Popular Antiquities_.]

=Needle=, Arch. An _obelisk_ (q.v.)

=Needle Point in relief.= To Venice belongs the invention of the two most perfect productions of the needle—“Point coupé,” and Venetian point in relief. Various other wonderful products of the needle are included under the general name of Venetian point, all of exquisite workmanship. The needle point in relief is made by means of cotton placed as thick as may be required to raise the pattern; an infinity of beautiful stitches are introduced into the flowers, which are surrounded by a pearl of geometric regularity. The engraving is an exquisite specimen of the fine raised needle point.

=Nef= or =Ship=. A costly and curious piece of plate for the table, used as an épergne in the Middle Ages. In the 16th century they were perfect models of actual ships, with masts, yards, shrouds, and sailors climbing in the rigging. They were filled with sweetmeats, and were sometimes put on wheels; and there is one at Emden in Hanover from the hull of which wine was drunk.

=Negative.= In Photography, a picture on glass having the lights and shadows reversed, from which _positives_ may be printed.

=Neginoth=, Heb. A general term for stringed musical instruments.

=Nehiloth=, Heb. (root _chalal_, to perforate). A general term for perforated wind instruments of music.

=Nelumbo=, Chinese. A fruit-tree closely connected with the Buddhist legends, and from its symbolical significance and adaptability to ornamentation, commonly represented on porcelain. (See _Jacquemart_, _Hist. de la Céramique_.)

=Nenia=, R. The funeral song which the hired mourners sang at a Roman funeral, in praise of the deceased. _Lessus_ was their wailing or cry of lamentation.

=Nenuphar= (It. _nenufar_). The great white water-lily of Europe.

=Neocori=, Gr. and R. (1) Originally sweepers of the temple. (2) In early times applied to the priests in charge of temples. (3) Under the Roman emperors, to all Asiatic cities which had temples dedicated to an emperor; it occurs in this sense (Νεωκόρος) on the coins of Ephesus, Smyrna, and other cities.

=Neoteric=, Gr. Of recent origin; modern.

=Nepaul Paper.= A strong unsized paper, made in Nepaul from the pulverized bark of the _Daphne papyracea_. Sheets of this paper are sometimes made many yards square.

=Nephrite.= A mineral. (See JADE.)

=Neptunalia.= Festivals celebrated at Rome on the 23rd of July, in honour of Neptune. The people built huts of branches and foliage about the streets.

=Nereids=, Gr. Nymphs of the sea, who were the constant attendants of Neptune.

=Nero Antico=, It. Antique marble of Egyptian and other ancient statuary, of an intense black, probably the result of ages of exposure, as no marble of the same intensity of blackness is found in any quarries. Marble, called also _nero antico_, of two degrees of beauty, is quarried at Aubert (Girons) in France; and the mausoleum of Napoleon I. is constructed of this stone.

=Nerved=, Her. Having fibres, as leaves.

=Nerves=, Arch. The name is sometimes applied to the ribs and mouldings on the side surface of a vault.

=Nessotrophium=, Gr. A place in a Roman villa for breeding domestic ducks. It was surrounded by a high wall, on which was a high ledge with nests for the birds. A pond was dug in the middle of the enclosure, which was planted with shrubs.

=Net Tracery=, Arch. A simple and beautiful form of tracery of the _Decorated_ period, consisting of a series of loops resembling the meshes of a net, each loop being quatrefoiled. An example occurs in the east cloister of Westminster Abbey.

=Nete=, Gr. The shortest string, or highest note, of the seven-stringed lyre. (See MESE.)

=Netherstocks=, O. E. The name given to _stockings_ in the 16th century, as continuations of the trunk-hose or _upper stocks_.

=Nethinim=, Heb. (from _nathan_, to give). The servants of the priests and Levites about the Temple.

=Nettle-cloth.= A material made in Germany of very thick cotton, used as a substitute for japanned leather, on the peaks of caps, &c.

=Network= (_filatorium opus_). An ancient method of embroidery in England, used for church use or household furniture, by darning or working the subject upon linen netting. This method chiefly prevailed in the 14th century.

=Neuma= or =Pneuma= (lit. a breath). A musical passage consisting of a number of notes sung to one syllable, or simply to a sound, as “āh” prolonged. “In hujus fine _neumatizamus_, id est jubilamus, dum finem protrahimus, et ei velut caudam accingimus.”

=Neutral Colour= is that resulting from a combination of blue, red, and yellow, resulting in grey.

=Neutral Tint.= An artificial pigment used in water-colours, composed of sepia, and indigo and other blues, with madder and other lakes; producing a scale of _neutral colours_.

=Neuvaines=, Fr. Chr. Set prayers repeated for _nine_ consecutive days.

=Nevers Faience.= (See NIVERNAIS.)

=Newcastle Glass.= A _crown_ glass, held the best for windows from 1728 to 1830, when it was superseded by the improved make of _sheet_ glass. It was of an ash colour, subject to specks, streaks, and other blemishes, and frequently warped.

=Newel=, Arch. The upright central pillar supporting a geometrical staircase.

=Newel Stairs=, Arch. Where the steps are _pinned_ into the wall, and there is no central pillar, the staircase is said to have an open or hollow newel. (See JOINERY.)

=Niche=, Arch. (It. _nicchia_, a sea-shell). A recess in a wall for a statue or bust. (Fig. 485.)

=Niche-vaulting=, Arch. (Germ. _Muschelgewölbe_). A form of roofing in a semi-cupola design, common in the choirs of churches.

=Nick=, =Old Nick=, O. E. (Icelandic _nikr_; A.S. _nicor_, a water-god). The devil.

=Nickel= (contraction of _Kupfernickel_, or Nick’s copper, a term of derision given to it by the German miners). A white or reddish-white metal, from which nickel-silver is made. It is used to a large extent in the arts, being remarkable for the peculiar whiteness and silver-like lustre which it communicates to other metals when alloyed with them.

=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.

=Nivarius= (saccus), R. A bag of snow used as a wine-cooler. (See COLLUM VINARIUM.)

=Nivernais Faience.= An important branch of the ceramic art, established in 1608 at Nevers in France by the brothers Conrade. (Fig. 486.)

=Nobbled Stone=, Arch. Stone roughly rounded at the quarry to diminish its bulk for transport.

=Noble.= A gold coin worth 6_s._ 8_d._ (Fig. 487.)

=Nodes.= In Astronomy, the two points where the orbit of a heavenly body intersects the ecliptic.

=Nodus=, Arch. The Latin name for a key-stone, or a _boss_ in vaulting.

=Nog=, O. E. Timbers built into walls to strengthen the structure. They show on the plastering of houses in ornamental patterns. In Kent these houses are called “wood noggen” houses.

=Noggin=, O. E. “A mug or pot of earth with a large belly and narrower mouth.”

=Nogging=, Arch. Brickwork in panels carried between quarters.

=Nome=, Egyp. (νομός). A division or district of Egypt; there were forty-four in all. Each nome was placed under the protection of a special divinity, and ruled by a resident military governor.

=Nonagon.= A nine-sided polygon.

=Nones.= (1) R. One of the three divisions of the Roman month; the ninth days before the IDES of each month. (2) Chr. One of the HOURS OF PRAYER (q.v.).

=Nonunia=, O. E. A quick time in music, containing nine crotchets between the bars. (_Halliwell._)

=Norman Architecture.= It was introduced into England at the Conquest, A. D. 1066, and was superseded in the 12th century by the Early English style. Solid massive masonry, round-headed doors and windows, and low square central tower are (broadly) its characteristics. Among details the zigzag and the billet mouldings are the most noticeable. (Fig. 488.)

=Norman Pottery=, Mediæval. The illustration is from a pavement of a church of the 12th century. “Nothing,” says Jacquemart, “is more curious than the study of these tiles, in which, with rudimentary means, art already begins to manifest its power. There, in a graceful chequer-work, the fleur-de-lis of France heightens at intervals a semé of trefoils and rosettes; scrolls of notched leaves combine in graceful borders; circles divided crossways receive in their sections stars and heraldic suns; here are armour-clad warriors, mounted upon horses richly caparisoned, &c.—all that picturesque fancy assisted by the resources of heraldry could invent to animate the cold compartments of the pavement, and give a meaning to the vast naves trodden every day by the Christian multitude.” (_Histoire de l’Art Céramique._) (Fig. 489.)

=Norns=, =Nornas=, Icelandic. The three Fates, whose names signify the Past, the Present, and the Future.

=Norroy King at Arms.= The third of the kings at arms, whose jurisdiction lies to the north of the Trent.

=North Side= of a church “was regarded as the source of the cold wind, and the haunt of Satan. In some Cornish churches there is an entrance called the devil’s door, adjoining the font, which was only opened at the time of the renunciation made in baptism, for the escape of the fiend. In consequence of these superstitions, and its sunless aspect, the northern parts of churchyards are usually devoid of graves.” (_Wallcott_, _Sacred Archæology_.)

=Norwegian Architecture.= The timber-built churches are of great interest, and exhibit the wonderful durability of the Norwegian pine. They are generally in the form of a cross, with a tower in the centre ending in a cupola or spire, and with high pitched roofs. The ornamental details are elaborate and richly carved. The whole is often painted of a rich brown colour; sometimes of a bright red. Some of these churches date from the 11th or 12th century, and are an imitation in wood of the masonic style of the period.

=Nosocomium=, R. (νοσο-κομεῖον). A hospital.

=Notatus=, R. (_noto_, to mark). A slave branded with a hot iron.

=Note of a Room.= The vibrations of the air in a chamber or vaulted space produce a musical _note_ proper to the dimensions and other conditions of the place, which a good musical ear can recognize and identify. [See _T. R. Smith’s Acoustics_, pp. 83–87.]

=Nottingham White.= White lead. (See CARBONATE OF LEAD.)

=November= (Lat. _novem_, nine). The _ninth_ month of the Roman year, which began with March. It consisted originally of thirty days, but Julius Cæsar added one to it. Augustus, however, reduced it to its original number.

=Nowed=, Her. Coiled in a knot, as a snake. The illustration (Fig. 490) is the ordinary device of the house of Savoy—the “true lovers’ knot;” with the Latin motto, “It binds but constrains not.”

=Nowel=, O. E. (Fr. _noel_, from _natalis_). A cry of joy; properly that at Christmas, of joy for the birth of the Saviour. It originally signified the feast of Christmas.

=Nubilarium=, R. A shed used as a barn; it was situated close to the threshing-floor.

=Numella=, =Numellus=, R. A kind of pillory for keeping men and animals in a fixed position. It was made use of in surgical operations, and as an instrument of torture.

=Numismatics= (_numisma_, coined money). The science of coins and medals. The earliest known coins were issued by the Greeks, probably in the 8th century B.C. (See the Article in the _Encyclopædia Britan._, 8th edition, from which reference can be taken to exhaustive treatises on the various ramifications of this science.)

=Nummud=, Persian. A carpet of felt much used in Persia.

=Nun’s Thread.= A kind of thread formerly made to a large extent in Paisley.

=Nun’s Work= (Fr. _œuvre de nonnain_). As early as the 14th century needlework was generally so described. Ancient lace is still so called in many parts of the country.

=Nundinæ= (_novemdinæ_; from _novem_, nine, and _dies_, days). Roman weeks; the nomenclature including the day before and that after the seven days. The name was given to the weekly _market_-days at Rome.

=Nupta=, R.(_nubo_, to wed). A married woman.

=Nuremberg Vase.= Fig. 491 is one of the gems, of the Renaissance period, issued from Nuremberg; a vase with portraits heightened with enamels and gold. (_Jacquemart_.)

=Nurhag= (Sardinian _Noraga_). Primitive buildings in the island of Sardinia, of remote antiquity, having turrets as high as 30 to 60 feet, and containing stones of 100 cubic feet each in their structure. [See _Waring_, _Stone Monuments_.]

=Nurspell.= An old English game like trap, bat, and ball. It is played with a _kibble_, a _nur_, and a _spell_. When the end of the _spell_ is struck with the _kibble_, the _nur_ rises into the air, &c.

=Nut.= In Christian symbolism, an emblem of the Divinity of Christ hidden in His manhood. St. Augustine has a long treatise on the symbolism of the husk, shell, and kernel of the nut. (_Serm. de temp. Dominic. ante Nativ._)

=Nut Oil.= This medium for colour-grinding is derived from the walnut; as a vehicle it is preferred to linseed oil, and is the quickest dryer. (See MEDIUMS, OILS.)

=Nutmeg Ornament=, Arch. A common feature in Early English work in the _north_ of England, but not in the south. It resembles half a nutmeg, and is carved at certain distances apart in the hollow of a dripstone at St. Mary’s Church, Nunmonkton, Yorkshire.

=Nuttoo=, Hind. A nose-stud or ornament worn by Indian women, often set with brilliants, rubies, emeralds, and pearls.

=Nymphæum=, =Nympheum= (νύμφαιον and νυμφεῖον). Literally, _a building consecrated to the nymphs_. It was a large and richly-decorated chamber, with columns, niches, and statues, and a fountain in the centre. Nymphæa were often erected near the head of a spring, and formed cool and agreeable retreats. Fig. 492 represents a portion of the ruins of the nymphæum of Egeria, near Rome; and Fig. 493 the interior of the nymphæum at Nismes, restored. In Christian times the fountains or cisterns common at the doors of churches were called _nymphæa_.

=Nymphs.= Inferior goddesses of the mountains, forests, waters, or meadows. Those presiding over rivers, &c., were OCEANIDES, NAIADS, NEREIDS; those over mountains, OREIADS; those over woods and trees, DRYADS and HAMADRYADS; those over valleys, NAPÆÆ, &c. They were represented in art as beautiful young women. The waters of Hades had their presiding nymphs, the AVERNALES.

O.

=O= was used as a numeral by the ancients to represent 11, and with a dash over it (Ō) to denote 11,000.

=O=, O. E. Anything circular. Shakspeare calls the stars “those fiery O’s.”

=Oak-apple Day=, O. E. The 29th of May, in commemoration of the escape of King Charles in the oak-tree.

=Oak-tree=, the emblem of virtue, force, and strength, is frequently introduced in ancient sculpture. In Christian art an attribute of St. Boniface, in allusion to his cutting down a Druidical oak.

=Oasis= (from the Coptic _ouah_, a resting-place). One of the verdant spots that occur at intervals in the deserts of Africa; hence any fertile spot in a desert, with the obvious symbolical application.

=Oast-house=, O. E. A kiln for drying hops.

=Oban.= The principal gold coin of Japan, worth about 4_l._ 2_s._

=Obba=, Gr. and R. (ἄμβιξ). A drinking-vessel of earthenware or wood, probably funnel-shaped; hence—

=Obbatus=, Gr. and R. Made in the shape of an _obba_, that is, terminating in a point. The term is often applied to the cap of the Dioscuri.

=Obelisk= (ὀβελίσκος, lit. a small spit). Also called a needle. A tall, rectangular, monolithic column, of slightly pyramidal shape, invented by the Egyptians; in nearly every case they are covered from the base to the top, and on all four sides, with hieroglyphic symbols. (Fig. 494.)

=Oberon.= The king of the fairies.

=Obex=, R. (_objicio_, to obstruct). Any contrivance to keep a door closed, such as a bolt, lock, latch, iron bar, &c.

=Oblata=, Chr. The sacred bread. This word was more commonly applied to the _unconsecrated_ loaf, and HOSTIA to the _consecrated_. (For particulars respecting the preparation and the form of _oblates_, see the article ELEMENTS in _Smith and Cheetham_, _Dict. of Christian Antiquities_.) In the same manner OBLATI were lay-brothers in a monastery who had not taken the vows.

=Oblate.= Flattened or shortened like the earth at the poles. The earth is an _oblate_ spheroid.

=Oblationarium=, Chr. A small table placed near the high altar, or at the end of one of the side aisles, on which the people laid their offerings. It was also used, when in the choir, to hold the sacred utensils in place of the _credence table_. In the Greek Church the _oblationarium_ is still used for the bread, wine, and sacred vessels required in the mass.

=Oble=, =Oblete= (Lat. _oblata_), O. E. The consecrated wafer distributed to communicants at mass.

“Ne Jhesu was nat the _oble_
That reysed was at the sacre.”
(_Harl. MS._)

Hence, a wafer-cake, sweetened with honey, and made of the finest wheaten bread.

=Oboe= or =Hautboy= (from Fr. _haut_, high, and _bois_, wood). A wind instrument like a flute, sounded through a reed.

=Obolo=, Mod. A copper coin, worth about a halfpenny, circulated in the Ionian Islands.

=Obolos=, Gr. (derived from ὀβολὸς, a brooch, originally). A small copper coin worth the sixth part of a drachm. The obolos in later times was of bronze; but in the best times of Athens it was of silver. Its value in the Æginetan standard was 1·166 of a penny.

=Obscœna=, Chr. Obscene representations frequently met with in Christian iconography, which, according to De Canmont, are “to warn the faithful that they ought to enter the temple with pure hearts, leaving outside all the passions that soil the soul.”

=Obsidian.= A volcanic glass found near volcanoes, used in antiquity for the manufacture of mirrors, axes, knives, &c. (See GLASS.)

=Obstragulum=, R. A long leather strap (_amentum_) worn as a fastening to the _crepida_.

=Obstrigillum=, R. A shoe, the sides of which were lengthened into a lappet over the instep.

=Obturaculum=, =Obturamentum=, R. (_obturo_, to stop up). A stopper for the neck of a bottle or the mouth of a vessel.

=Obverse.= Of a coin, the face, or side which bears the principal symbol. The other side is the REVERSE.

=Ocal=, Span. Coarse silk.

=Occabus=, R. (ὄκκαβος). A kind of spoon.

=Occidental Diamond.= A precious stone of inferior hardness and beauty.

=Occultation.= The disappearance or eclipse of one heavenly body behind another.

=Ocellata=, R. (lit. marked with _ocelli_ or spots). Marbles used as playthings by children.

=Ocellated.= Full of eyes; said of a peacock’s tail. (See Fig. 398.)

=Ochre.= Argillaceous earth of different colours which, when finely ground, is used as a pigment. _Red ochre_ is a form of specular iron ore; _brown ochre_ is a variety of hæmatite. The _yellow ochres_ become red when calcined, but the finest reds are made from those which are brown in the bed. Native red ochre is called _red chalk_ or _reddle_ in England. _Spanish Brown_, _Indian Red_, _Venetian Red_, and the yellow ochres have nearly the same composition. The other ochres are known as _Oxford_, _Roman_, and _stone ochres_, and as _terra di Sienna_ and _umber_. They are all valuable and durable pigments for oil, water, or enamel painting. (See AMATITA.)

=Ocrea=, R. A greave; a piece of armour which covered the shin-bone from below the knee to the ankle. It was generally richly ornamented by designs embossed or chased upon it. (Modern JAMBES.)

=Octagon.= A figure of eight equal sides, considered as an emblem of regeneration; consequently the proper form for baptistries and fonts. (_Fairholt._)

=Octahedron.= A solid contained by eight equal sides, which are equilateral triangles.

=Octastyle=, R. (ὀκτά-στυλος). An _octastyle_ portico is a portico having eight columns in front; _octastyle_ pediment, a pediment supported by eight columns. The pediment of the Parthenon at Athens, from which the Elgin Marbles come, is an _octastyle_.

=Octave.= (1) In Music, the longest interval in the diatonic scale; as from _do_ to _do_, or C to C. (2) Chr. Eight days, or the eighth day after a Church festival (the festival being included) kept as a repetition or prolongation of the festival. It is a Western custom unknown to the Eastern Church.

=October.= The eighth month of the old Roman year, but the tenth in the calendar of Numa, Julius Cæsar, &c. It was sacred to Mars, and a horse called the _October equus_ was annually sacrificed to Mars.

=Octofoil=, Her. A double _quatrefoil_; the _difference_ of a ninth son.

=Octophoron= or =Octaphoron=, Gr. and R. (ὀκτώφορον). A litter (_lectica_) borne by eight slaves.

=Ocularium=, Med. Lat. The narrow slit or opening for the sight in a helmet. (See Fig. 495.)

=Oculus=, Chr. A round window of frequent occurrence in the tympanum of the pediment in Latin basilicas, and occasionally in certain churches of the 11th century.

=Ode= (ᾠδὴ, a song). A short lyrical poem, intended to be sung to the accompaniment of an instrument, especially the _lyre_; hence the expression _lyric_ poetry.

=Odeon= (ᾠδεῖον; ᾠδὴ, a song). A small theatre at Athens, built by Pericles for musical performances. By analogy, the name was applied to any theatre built on a circular plan and covered with a roof, like that of Athens, shown in Fig. 496.

=Œcos=, =Œcus=, Gr. (οἶκος). A Greek house; the term, however, denoted rather a large apartment resembling the atrium, but entirely shut in, that is to say, without impluvium. In Fig. 497, A is the œcus; B, C, two rooms forming offices; D, a tablinum; E, a portico; G, the entrance to the house; H, work-rooms; J, the triclinium. _Œcus tetrastylos_ was a house in which four columns supported the roof; _œcus Corinthius_, having one order of columns supporting an architrave, cornice, and an arched roof; _œcus Egyptius_, in which the pillars supported a gallery with a paved floor, forming a walk round the apartment; above these pillars others were placed, one-fourth less in height; and between the upper columns were placed windows; and the _œcus Cyzicenus_, which looked to the north, and, if possible, faced gardens, to which it opened by folding doors, was a summer-house. (See DOMUS.)

=Œil-de-bœuf=, Arch. A small round or oval window in a roof.

=Œillets.= (See OILLETS.)

=Œnochoê= (Gr. οἶνος, wine, and χέω, to pour). An earthen vase used to take the wine out of the crater and distribute it into cups. It is the vase carried by the goddesses, and used for libations. (Figs. 498, 498 a.)

=Œnophorum=, Gr. and R. (οἰνοφόρον). A light case or basket for carrying wine.

=Œnopolium=, Gr. and R. (οἰνοπώλιον). The shop of a dealer who sold wine to be carried away; distinct from the _taberna meritoria_ or _deversoria_, which was a public tavern.

=Offendix=, R. A string by which the _apex_, or cap worn by the flamens, Salians, or other members of priestly colleges, was fastened under the chin.

=Offertoria=, Chr. (1) The anthems sung in a Christian church while the oblations were received; mentioned by Isidorus, A. D. 595: “Offertoria quæ in sacrificiorum honore canuntur.” (2) Large plates, which, in the Christian churches of Gaul, served to collect the bread which the Christians had just laid on the altar. A beautiful specimen of such dishes, found in Siberia in 1867, and described by Rossi, is 6 inches in diameter, and weighs 1½ lbs. It has a relief in _repoussé_ work, consisting of a cross planted on a small globe studded with stars, beneath which issue the four rivers of Paradise; and on either side stand two nimbed angels, holding a rod in the left hand, and raising their right hand towards the cross in token of adoration. De Rossi regards this dish as the work of Byzantine goldsmiths of the 6th century. (3) At Rome, acolytes went in and out among the people, and collected the offerings in napkins of line linen or richer material called also _offertoria_.

=Offertories=, in Egyptian archæology, are offerings made to the gods, of various shapes; such as outstretched hands supporting a cup, or spoons of ivory, wood, or bronze, the handle of which is formed by a human figure.

=Officina=, R. A workshop, in contradistinction to _taberna_, a store, and _apotheca_, a shop; thus, _officina ærariorum_ was a goldsmith’s workshop; _officina fullonum_, a fuller’s establishment.

=Offuscati.= One of the Italian literary academies. They bore for their device a bear, roused from his natural heaviness by the stings of bees, with the motto, “Stings (or points) will sharpen steel.” (Fig. 499.)

=Ogam=, Celtic. The sacred writing of the Druids. (Cf. OGHAM.)

=Ogee Arch= or =Contrasted Arch= or =Moulding=, Arch. An arch or moulding described by means of four centres, so as to be alternately concave and convex. It was frequently employed in fifteenth-century monuments, and its constant recurrence in the _later Gothic_ or _flamboyant_ architecture has given rise to its French name of _ogival_.

=Ogham.= A kind of shorthand writing or cipher in use among the ancient Irish. (_S._)

=Ogivale=, Fr. A French architectural term of constant occurrence, applied to the architecture of the mediæval period in France, during which the _pointed arch_ was used.

=Ogive=, Fr. Arch. A _pointed_ arch; _not_ the OGEE.

=Ogivette=, Arch. A small ogee.

=Ogress=, Her. A pellet or black roundle.

=Oil Painting= was introduced in Flanders by the brothers Van Eyck in 1410, and in Italy by Antonello da Messina in or about 1455.

=Oillets= or =Oylets=. Loopholes.

=Oils.= The fixed oils used in painting are _linseed_, _walnut_, and _poppy_, purified and rendered drying by the addition of _litharge_. They should be pale in colour, limpid, and transparent, and should dry quickly: _nut oil_ in a few hours, _linseed_ in a day, and _poppy oil_ in thirty-six to forty hours. The essential oils used in painting are _turpentine_, for diluting the pigments ground in oil, and _spike_, or _lavender_, for wax and enamel painting.

=Oinerusis=, Gr. (οἰν-ήρυσις). (See ARYSTICHOS.)

=Ointment-box=, in Christian art, is the attribute of St. Mary Magdalene, St. Joseph of Arimathæa, and other saints.

=Oiron=, a small town in France (so named from the flocks of geese which circle round it _Oi-rond_ in winter), is the place where the fine faiences, usually called Henri II. ware, were made. “Here is France,” says M. Jacquemart, “in the 16th century in possession of a pottery, the discovery of which is attributed 200 years later to England.” There are only about fifty pieces known, five of which may be seen in the South Kensington Museum.

=Okel=, Egyp. A caravanserai. A large covered court surrounded by two stories of galleries, of which the lower is used as shops, &c., and the upper one as lodging-rooms.

=Oldham.= A coarse kind of cloth originated at Oldham in Norfolk, _temp._ Richard II.

=Olibanum.= A gum-resin used for incense.

=Oliphant=, A.S. An elephant; hence a hunting-horn of ivory.

=Olive.= A blue-grey colour; violet mixed with green.

=Olive=(-tree). (1) In Christian art, the emblem of peace and concord, and frequent on early Christian tombs in the catacombs, with or without the dove. (2) Arch. Its leaf was introduced into sculpture by the ancients, in wreaths or garlands. The Corinthian order is enriched with _olive_-leaves, as are almost all the antiques at Rome of this order. (3) R. The _corona oleagina_, an honorary wreath made of olive-leaves, was conferred by the Romans on soldiers and commanders through whose instrumentality a triumph had been obtained when they were not personally present in the action. (4) Gr. It was the _olive_-tree that Minerva caused to spring from the ground in the citadel at Athens. (5) The colour and grain of the wood, and of the root portion especially, are very beautiful, and valuable for decorative and cabinet-work.

=Olivette.= A Flemish name for _poppy oil_.

=Olivine.= A variety of _chrysolite_ of a dark green, commonly called bottle-green colour.

=Olla=, R. An earthenware vessel of very common make. It resembled our flower-pots, but had swelling sides, and was covered with a lid. It was used for cooking meat and vegetables and for preserving grapes (_uva ollaria_), and as a cinerary urn (_olla ossuaria_ or _cineraria_). Hence—

=Olla-podrida=, Sp. A stew of meat and vegetables mixed, common in Spain. The word is used to describe any other incongruous mixture.

=Ollarium=, R. A niche in a sepulchral chamber, in which the _olla ossuaria_ was placed. (See CINERARIUM, Fig. 160.)

=Olpê=, Gr. (ὄλπη). A kind of _aryballos_ with a curved handle, but no spout (originally a leather oil-flask).

=Olympiad=, Gr. (Ὀλυμπίας). The period of four years between two consecutive celebrations of the Olympic games. The first Olympiad began B.C. 776.

=Olympic Games=, Gr. Games instituted by Hercules in honour of Jupiter Olympius; they were the most ancient and celebrated in all Greece. They derived their name from Olympia, in Greece, where they were celebrated. They were finally suppressed by Theodosius, A. D. 394.

=Ombre.= A kind of damask.

=Ombros.= The name for a particular quality of _madder_.

=Omophagi=, Gr. (ὠμο-φάγοι, sc. δαῖτες, i. e. flesh-eating banquets). Festivals held at Chio and Tenedos in honour of Bacchus.

=Omophorion.= (1) An article of female dress, worn on the _shoulders_. (2) A vestment of the Greek Church, consisting of a long woollen band with embroidered crosses. It is typical of the lost sheep borne home on the shoulders of the Shepherd.

=Onager=, =Onagrus=, R. An engine for hurling stones of great size.

=Onicolo= or =Nicolo=. A variety of the onyx, with a deep-brown ground, on which is a band of bluish white, used for making cameos.

=Onocentaurs.= Fabulous animals, half man, half ass.

=Onychomancy= (_onyx_, a nail). Divination by means of the marks on the nails of the hands.

=Onyx= (ὄνυξ, a finger-nail). (1) A general name for the varieties of the agate which consist of alternate layers of white, brown, or black, greatly valued by the ancients for cameos. In the Christian symbolism the onyx typifies innocence and candour. (See ONICOLO.) (2) The name has also been applied by the ancients to Oriental alabaster. (3) Onyx marble was a name given to Algerian marble from Oran, of which “pure white, brilliant red, golden yellow, and hues of green, with every variety of striation and flocculence, exist.” [See the _Building News_, xiv. 489.]

=Opa=, =Opê=, Gr. Arch. (ὀπή). A cavity in which a tie-beam (_tignum_) rests; whence the space included between two ὀπαὶ or _tigna_ was called _metopa_ or _intertignum_.

=Opacity.= Want of transparency.

=Opaion=, Gr. Arch. The panels on a ceiling formed by the intersection of its beams.

=Opal.= A semi-transparent stone, remarkable for the play of colours that it exhibits. Three varieties are, the _oriental opal_, called also the _noble_ opal and the _harlequin_ opal, remarkable for its flashes of brilliant colours having a triangular disposition. The affection that the ancients entertained for this beautiful gem was unbounded. The Roman senator Nonnius preferred exile to parting with a brilliant opal the size of a filbert which Marc Antony coveted. The _fire opal_ is furnished principally by Mexico. Its colour, more pronounced than that of the _oriental_ opal, and the carmine or vinous red tint of its fires, permit it to be easily recognized. The _common opal_ displays very little fire; its colour is milk-white, which, joined to a texture extremely homogeneous, renders it semi-transparent. [_L. Dieulafait._]

=Opal Glass=, called also Milk-white Glass; prepared for globes to lamps, &c.

=Opales=, =Opalia=, R. Festivals of Ops, the wife of Saturn, which were held every year on the fourteenth of the calends of January (19th of December).

=Opalescent.= Having a play of colours like the _opal_.

=Open-tide=, O. E. The season between Epiphany and Ash-Wednesday, when marriages were publicly solemnized.

=Opera.= A lyrical drama set to music; originated at Florence in the 16th century. [Consult _Doni_ (passim), _Arteaga Manfredini_, _Signorelli_, &c.; also _Dr. Burney’s Tours and Correspondence_, and _Grimm’s Correspondence_.]

=Operculum=, R. A cover for any kind of earthenware vessel.

=Ophicleide= (ὄφις, a serpent, and κλεὶς, a key). A wind instrument of brass or copper made in the form of a serpent. Generally, the bass of a military band.

=Ophiomancy=, Gr. Divination by snakes.

=Ophiomorphous.= Snake-shaped.

=Ophite= or =Ophiolite=. Green porphyry or SERPENTINE.

=Ophites=, Chr. A sect which arose in the 2nd century in the Christian Church. They believed that the Serpent who tempted Eve was Christ himself. They are also called SERPENTINIANS. (_S._)

=Opima Spolia=, R. The “spoils of honour,” consisting of armour set up as a trophy and dedicated in the temple of Jupiter Feretrius at Rome. These were spoils taken from the chief of a hostile army, who had been killed by the hand of a Roman general. Plutarch asserts that the _spolia opima_ were actually taken only three times.

=Opinicus=, Her. A fabulous heraldic monster; a dragon before and a lion behind, with a camel’s tail.

=Opisthodomos=, Gr. (ὀπισθό-δομος). Latin, =Posticum=. A small chamber placed at the back of a temple, to which the priests alone had access.

=Oporotheca=, Gr. (ὀπωρο-θήκη). A storehouse for fruits.

=Oppidan.= At Eton College, a boy who is not a king’s scholar, and boards in the town.

=Oppidum=, R. A fortified town, and thence the mass of buildings occupying the extremity of a circus, in which were the stalls for the chariots and horses (_carceres_). Fig. 502 gives a representation of the _oppidum_ in the circus of Caracalla.

=Optical Correction= is a name given to the task of adapting art objects, or architectural proportions and ornaments, to the circumstances of distance or comparison in which they are to be exhibited. Belzoni observes that the heads of colossal Egyptian statues are proportionally larger than the lower members. (For numerous examples of this contrivance, see the article in the _Architectural Publication Society’s Dictionary_.)