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 with layers of composition and stars alternately. These stars are simply balls of some special composition, usually containing metallic filings, made up with gum and spirits of wine, cut to the required size and shape, dusted with gunpowder and dried. They are discharged like blazing bullets several feet into the air, and produce a beautiful effect, which may be enhanced by packing stars of differently coloured fire in one case. Gerbes are choked cases, not unlike Roman candles, but often of much larger size. Their fire spreads like a sheaf of wheat. They may be packed with variously coloured stars, which will rise 30 ft. or more. Lances are small straight cases charged with compositions like those used for making stars. They are mostly used in complex devices, for which purpose they are fixed with wires on suitable wooden frames. They are connected by leaders, i.e. by quick-match enclosed in paper tubes, so that they can be regulated to take fire all at the same time, singly, or in detachments, as may be desired. The devices and “set pieces” constructed in this way are often of an extremely elaborate character; and they include all the varieties of lettered designs, of fixed suns, fountains, palm-trees, waterfalls, mosaic work, Highland tartan, portraits, ships, &c.

Rotating Fireworks.—Pin or Catherine wheels are long paper cases filled with a composition by means of a funnel and packing-wire and afterwards wound round a disk of wood. This is fixed by a pin, sometimes vertically and sometimes horizontally; and the outer primed end of the spiral is lit. As the fire escapes the recoil causes the wheel to revolve in an opposite direction and often with considerable velocity. Pastiles are very similar in principle and construction. Instead of the case being wound in a spiral and made to revolve round its own centre point, it may be used as the engine to drive a wheel or other form of framework round in a circle. Many varied effects are thus produced, of which the fire-wheel is the simplest. Straight cases, filled with some fire-composition, are attached to the end of the spokes of a wheel or other mechanism capable of being rotated. They are all pointed in the same direction at an angle to the spokes, and they are connected together by leaders, so that each, as it burns out, fires the one next it. The pieces may be so chosen that brilliant effects of changing colour are produced; or various fire-wheels of different colours may be combined, revolving in different planes and different directions—some fast and some slowly. Bisecting wheels, plural wheels, caprice wheels, spiral wheels, are all more or less complicated forms; and it is possible to produce, by mechanism of this nature, a model in fire of the solar system.

Ascending Fireworks.—Tourbillions are fireworks so constructed as to ascend in the air and rotate at the same time, forming beautiful spiral curves of fire. The straight cylindrical case is closed at the centre and at the two ends with plugs of plaster of Paris, the composition occupying the intermediate parts. The fire finds vent by six holes pierced in the case. Two of these are placed close to the end, but at opposite sides, so that one end discharges to the right and the other to the left; and it is this which imparts the rotatory motion. The other holes are placed along the middle line of what is the under-surface of the case when it is laid horizontally on the ground; and these, discharging downwards, impart an upward motion to the whole. A cross piece of wood balances the tourbillion; and the quick-match and touch-paper are so arranged that combustion begins at the two ends simultaneously and does not reach the holes of ascension till after the rotation is fairly begun. The sky-rocket is generally considered the most beautiful of all fireworks; and it certainly is the one that requires most skill and science in its construction. It consists essentially of two parts,—the body and the head. The body is a straight cylinder of strong pasted paper and is choked at the lower end, so as to present only a narrow opening for the escape of the fire. The composition does not fill up the case entirely, for a central hollow conical bore extends from the choked mouth up the body for three-quarters of its length. This is an essential feature of the rocket. It allows of nearly the whole composition being fired at once; the result of which is that an enormous quantity of heated gases collects in the hollow bore, and the gases, forcing their way downwards through the narrow opening, urge the rocket up through the air. The top of the case is closed by a plaster-of-Paris plug. A hole passes through this and is filled with a fuse, which serves to communicate the fire to the head after the body is burned out. This head, which is made separately and fastened on after the body is packed, consists of a short cylindrical paper chamber with a conical top. It serves the double purpose of cutting a way through the air and of holding the garniture of stars, sparks, crackers, serpents, gold and silver rain, &c., which are scattered by bursting fire as soon as the rocket reaches the highest point of its path. A great variety of beautiful effects may be obtained by the exercise of ingenuity in the choice and construction of this garniture. Many of the best results have been obtained by unpublished methods which must be regarded as the secrets of the trade. The stick of the sky-rocket serves the purpose of guiding and balancing it in its flight; and its size must be accurately adapted to the dimensions of the case. In winged rockets the stick is replaced by cardboard wings, which act like the feathers of an arrow. A girandole is the simultaneous discharge of a large number of rockets (often from one hundred to two hundred), which either spread like a peacock’s tail or pierce the sky in all directions with rushing lines of fire. This is usually the final feat of a great pyrotechnic display.

See Chertier, Sur les feux d’artifice (Paris, 1841; 2nd ed., 1854); Mortimer, Manual of Pyrotechny (London, 1856); Tessier, Chimie pyrotechnique, ou traité pratique des feux colorés (Paris, 1858); Richardson and Watts, Chemical Technology, s.v. “Pyrotechny” (London, 1863–1867); Thomas Kentish, The Pyrotechnist’s Treasury (London, 1878); Websky, Luftfeuerwerkkunst (Leipzig, 1878).

FIRM, an adjective originally indicating a dense or close consistency, hence steady, unshaken, unchanging or fixed. This word, in M. Eng. ferme, is derived through the French, from Lat. firmus. The medieval Latin substantive firma meant a fixed payment, either in the way of rent, composition for periodic payments, &c.; and this word, often represented by “firm” in translations of medieval documents, has produced the English “” (q.v.). From a late Latin use of firmare, to confirm by signature, firma occurs in many Romanic languages for a signature, and the English “firm” was thus used till the 18th century. From a transferred use came the meaning of a business house. In the Partnership Act 1890, persons who have entered into partnership with one another are called collectively a firm, and the name under which their business is carried on is called the firm-name.

FIRMAMENT, the sky, the heavens. In the Vulgate the word firmamentum, which means in classical Latin a strengthening or support (firmare, to make firm or strong) was used as the equivalent of  (, to make firm or solid) in the LXX., which translates the Heb. rāqīyaʽ. The Hebrew probably signifies literally “expanse,” and is thus used of the expanse or vault of the sky, the verb from which it is derived meaning “to beat out.” In Syriac the verb means “to make firm,” and is the direct source of the Gr.  and the Lat. firmamentum. In ancient astronomy the firmament was the eighth sphere containing the fixed stars surrounding the seven spheres of the planets.

FIRMAN (an adaptation of the Per. fermān, a mandate or patent, cognate with the Sanskrit pramāna, a measure, authority), an edict of an oriental sovereign, used specially to designate decrees, grants, passports, &c., issued by the sultan of Turkey and signed by one of his ministers. A decree bearing the sultan’s sign-manual and drawn up with special formalities is termed a hatti-sherif, Arabic words meaning a line, writing or command, and lofty, noble. A written decree of an Ottoman sultan is also termed an irade, the word being taken from the Arab. irādā, will, volition, order.

FIRMICUS, MATERNUS JULIUS, a Latin writer, who lived in the reign of Constantine and his successors. About the year 346 he composed a work entitled De erroribus profanarum religionum, which he inscribed to Constantius and Constans, the sons of Constantine, and which is still extant. In the first part (chs. 1-17) he attacks the false objects of worship among the Oriental cults; in the second (chs. 18-29) he discusses a number of formulae and rites connected with the mysteries. The whole tone of the work is fanatical and declamatory rather than argumentative, and is thus in such sharp contrast with the eight books on astronomy (Libri VIII. Matheseos) bearing the same author’s name, that the two works have usually been attributed to different writers. Mommsen (Hermes vol. 29, pp. 468-472) has, however, shown that the astronomy—a work interfused with an urbane Neoplatonic spirit—was composed about 336 and not in 354 as was formerly held. When we add to this the similarity of style, and the fact that each betrays a connexion with Sicily, there is the strongest reason for claiming the same author for the two books, though it shows that in the 4th century acceptance of Christianity did not always mean an advance in ethical standpoint.

The Christian work is preserved in a Palatine MS. in the Vatican library. It was first printed at Strassburg in 1562, and has been reprinted several times, both separately and along with the writings of Minucius Felix, Cyprian or Arnobius. The most correct editions are those by Conr. Bursian (Leipzig, 1856), and by C. Halm, in his Minucius Felix (Corp. Scr. Eccl. Lat. ii.), (Vienna, 1867). The Neoplatonist work was first printed by Aldus Manutius in 1501, and has often been reprinted. For full discussions see G. Ebert, ''Gesch. der'' ''chr. lat. Litt.'', ed. 1889, p. 129 ff.; O. Bardenhewer, Patrologie, ed. 1901, p. 354.