= of his court. The pope is the ordinarius of the whole Roman | On the other hand, the development of the gun has always Catholic Church, and is sometimes described as ordinarius had an upward tendency, which of late years has been very erdinariorum. Similarly in the Church of England the king is marked, the demand for the increase of energy has kept pace legally the supreme ordinary, as the source of jurisdiction. with-or rather in recent times may be said to have causedThe use of the term ordinary is not confined to ecclesiastical improvements in metallurgical science. jurisdiction. In the civil law the judex ordinarius is a judge who has regular jurisdiction as of course and of common right as opposed to persons extraordinarily appointed. The term survived throughout the middle ages wherever the Roman law gained a foothold. In the Byzantine empire it was applied to any one filling a regular office (e.g. varоs opôivápios = consul ordinarius, apxwv opowápios praefectus ordinarius); but it also occasionally implied rank as distinct from office, all those who had the title of clarissimus being sometimes described as ὀρδινάριοι. In England the only case of the term being employed in its civil use was that of the office of judge ordinary created by the Divorce Act of 1857, a title which was, however, only in existence for the space of about eighteen years owing to the incorporation of the Divorce Court with the High Court of Justice by the Judicature Act 1875. But in Scotland the ordinary judges of the Inner and Outer Houses are called lords ordinary, the junior lord ordinary of the Outer House acts as lord ordinary of the bills, the second junior as lord ordinary on teinds, the third junior as lord ordinary on Exchequer causes. In the United States the ordinary possesses, in the states where such an officer exists, powers vested in him by the constitution and acts of the legislature identical with those usually vested in the courts of probate. In South Carolina he was a judicial officer, but the office no longer exists, as South Carolina has now a probate court. In the German universities the Professor ordinarius is the occupant of one of the regular and permanent chairs in any faculty. ORDINATE, in the Cartesian system of co-ordinates, the distance of a point from the horizontal axis (axis of x) measured parallel to the axis of y. Thus PR is the ordinate of P. The word appears to have been first used by René Descartes, and to be derived from lineae ordinatae, a term used by Roman surveyors for parallel lines. (See GEOMETRY: Analytical.) R ORDNANCE (a syncopated form of "ordinance" or "ordonnance," so spelt in this sense since the 17th century), a general term for great guns for military and naval purposes, as opposed to small arms" and their equipment; hence the term also includes miscellaneous stores under the control of the ordnance department as organized. In England the MasterGeneral of the Ordnance, from Henry VIII's time, was head of a board, partly military, partly civil, which managed all affairs concerning the artillery, engineers and matériel of the army; this was abolished in 1855, its duties being distributed. The making of surveys and maps (see MAP) was, for instance, handed aver eventually (1889) to the Board of Agriculture, though the term "ordnance survey" still shows the origin. I. HISTORY AND CONSTRUCTION The efficiency of any weapon depends entirely on two factors: (1) its power to destroy men and material, (2) the moral effect upon the enemy. Even at the present day the moral effect of gun fire is of great importance, but when guns were first used the noise they made on discharge must have produced a bewildering fear in those without previous experience of them; more especially would this be the case with horses and other animals. Villani wrote of the battle of Cressy that the " English guns made a noise like thunder and caused much loss in men and horses" (Hime, Proc. R. A. Institution, vol. 26). Now, the moral effect may be considered more or less constant, for, as men are educated to the presence of artillery, the range of guns, their accuracy, mobility and on shore their invisibility, so increase that there is always the ever present fear that the stroke will fall without giving any evidence of whence it came. The evolution of ordnance may be divided roughly into three epochs. The first includes that period during which stone shot were principally employed; the guns during this period (1313 to 1520) were mostly made of wrought iron, although the art of casting bronze was then well known. This was due to the fact that guns were made of large size to fire heavy stone shot, and, in consequence, bronze guns would be very expensive, besides which wrought iron was the stronger material. The second epoch was that extending from 1520 to 1854, during which cast iron round shot were generally employed. In this epoch, both bronze and cast iron ordnance were used, but the progress achieved was remarkably small. The increase of power actually obtained was due to the use of corn, instead of serpentine, powder, but guns were undoubtedly much better proportioned towards the middle and end of this period than they were at the beginning. The third or present epoch may be said to have commenced in 1854, when elongated projectiles and rifled guns were beginning to be adopted. The rapid progress made during this period is as remarkable as the unproductiveness of the second epoch. Even during recent years the call for greater power has produced results which were believed to be impossible in 1890. The actual date of the introduction of cannon, and the country in which they first appeared, have been the subject of much antiquarian research; but no definite conclusion has been arrived at. Some writers suppose (see Brackenbury, "Ancient Cannon in Europe" in Proc. Royal Artillery Inst., vol. iv.) that gunpowder was the result of a gradual development from incendiary compounds, such as Greek and sea fire of far earlier times, and that cannon followed in natural sequence. Other writers attribute the invention of cannon to the Chinese or Arabs. In any case, after their introduction into Europe a comparatively rapid progress was made. Early in the 14th century the first guns were small and vase shaped; towards the end they had become of huge dimensions firing heavy stone shot of from 200 to 450 lb weight. The earliest known representation of a gun in England is contained in an illuminated manuscript "De Officiis Regum at Christ Church, Oxford, of the time of Edward II. (1326). This clearly shows a knight in armour firing a short primitive weapon shaped something like a vase and loaded with an incendiary arrow. This type of gun was a muzzle loader with a vent channel at the breech end. There seems to be undoubted evidence that in 1338 there existed breech-loading guns of both iron and brass, provided with one or more movable chambers to facilitate loading (Proc. R. A. I., vol. iv. p. 291). These firearms were evidently very small, as only 2 lb of gunpowder were provided for firing 48 arrows, or about seven-tenths of an ounce for each charge. The great Bombarde of Ghent, called "Dulle Griete " (fig. 1) is believed to belong to the end of the century, probably about which weighs about 13 tons, is formed of an inner lining of wrought iron longitudinal bars arranged like the staves of a cask and welded together, surrounded by rings of wrought iron driven or shrunk on. The chamber portion is of smaller diameter, and some suppose it to be screwed to the muzzle portion. The length of the gun is 197 in., the diameter of the bore 25 in., and the chamber 10 in. at the front and tapering to 6 in. diameter at the breech end. It fired a granite ball weighing about 700 lb. Two wrought iron guns left by the English in 1423 when they had to raise the siege of Mont St Michel in Normandy belong to about the same period; the larger of these guns has a bore of 19 in. diameter. Mons Meg" (fig. 2) in Edinburgh Castle is a wrought iron gun of a little later period; it is built up in the same manner of iron bars and external rings. It has a calibre of 20 in. and fired a granite shot weighing 330 lb. FIG. 2.-Mons Meg. Bronze guns of almost identical dimensions to the "Dulle Griete were cast a little later (1468) at Constantinople (see Lefroy, Proc. R. A. I., vol. vi.). One of these is now in the Royal Military Repository, Wollwich. It is in two pieces screwed together: the front portion has a calibre of 25 in. and is for the reception of the stone shot, which weighed 672 lb; and a rear portion, forming the powder chamber, of ro in. diameter. The whole gun weighs nearly 18 tons. To give some idea of the power of these guns, the damage done by them to Sir John Duckworth's squadron in 1807 when the Dardanelles were forced may be instanced. In this engagement six men-of-war were more or less damaged and some 126 men were killed or wounded. The guns were too unwieldy to lay for each round and were consequently placed in a permanent position; they were often kept loaded for months. The 16th century was remarkable from the fact that the large bombard type was discarded and smaller wrought iron guns were made. This was due to the use of iron projectiles, which enabled a blow to be delivered from a comparatively small gun as destructive as that from the very weighty bombards throwing stone shot. Bronze guns also now came into great favour. They were first cast in England in 1521 (Henry VIII.), and iron cannon about 1540, foreign founders being introduced for the purpose of teaching the English the art. The "Mary Rose," which sank off Spithead in 1545, had on board both breech-loading wroughtiron and muzzle-loading bronze guns. The smaller guns cast at this period were of considerable length, probably on account of the large charges of meal powder which were fired. The long bronze gun in Dover Castle known as Queen Elizabeth's pocket pistol" has a calibre of 4.75 in.; its bore is 23 ft. 1 in. long or 58 calibres, but its total length including the cascable is 24 ft. 6 in. It was cast at Utrecht in 1544 and presented by Charles V. to Henry VIII. Little or no classification of the various types of guns was attempted during the 15th century. The following century saw some attempt made at uniformity and the division of the several calibres into classes, but it was not until about 1739, when Maritz of Geneva introduced the boring of guns from the solid, that actual uniformity of calibre was attained, as up to this date they were always cast hollow and discrepancies naturally occurred. In France organization was attempted in 1732 by Vallière, but to Gribeauval (q.v.) is due the credit of having simplified artillery and introduced great improvements in the equipment. It is not possible to compare properly the power of the earlier guns; at first small and feeble, they became later large and unwieldy, but still feeble. The gunpowder called "serpentine " often compounded from separate ingredients on the spot at the time of loading, burnt slowly without strength and naturally varied from round to round. The more fiercely burning granulated or corned powder, introduced into Germany about 1429, and into England shortly after, was too strong for the larger pieces of that date, and could be used only for small firearms for more than a century after. These small guns were often loaded with a lead or lead-coated ball driven down the bore by hammering. The bronze and cast iron ordnance which followed in the 16th century were strengthened in the 17th century, and so were more adapted to use the corned powder. By this means some access of energy and greater effective ranges were obtained. In the 18th century and in the first half of the 19th no change of importance was made, Greater purity of the ingredients and better methods of manufacture had improved gunpowder; the windage between the shot and the bore had also been reduced, and guns had been strengthened to meet this progress, but the principles of construction remained unaltered until the middle of the 19th century. Metallurgical science had made great progress, but cast iron was still the only metal considered suitable for large guns, whilst bronze was used for field guns. Many accidents, due to defects developing during practice, had, however, occurred, in order to prevent which experimental guns constructed of stronger material such as forged iron and steel had been made. Some of these weapons were merely massive solid blocks, with a hole bored in for the bore, and only withstood a few rounds before bursting. This result was attributed to the metal being of an indifferent quality-quite a possible reason as the treatment of large masses of steel was then in its infancy, and even with the best modern appliances difficulties have always existed in the efficient welding of large forgings of iron. Forged iron, however, always gave some evidence of its impending failure whereas the steel burst in pieces suddenly; steel was, therefore, considered too treacherous a material for use in ordnance. This view held for many years, and steel was only again employed after many trials had been made to demonstrate its reliability. It will be seen later that the ill success of these experiments was greatly due to a want of knowledge of the correct principles of gun construction. The progress made since 1854 is dependent on and embraces improvements in gun construction, rifling and breech mechanisms. Old Equip ments. Considerable obscurity exists as regards the means adopted for mounting the first cannon. From illuminations in contemporary manuscripts it appears that the earliest guns, which were trunnionless, were simply laid on the ground and supported by a timber framing at each side, whilst the flat breech end rested against a strong wood support let into the ground to prevent recoil. This arrangement was no doubt inconvenient, and a little later small cannon were fastened in a wooden stock by iron bands; larger guns were supported in massive timber cradles (fig. 3) and Redrawn from Mallet's Construction of Artillery. FIG. 3.-Primitive Gun-mounting. secured thereto by iron straps or ropes. The ponderous weight to be moved and the deficiency of mechanical means prevented these large cannon and their cradles from being readily moved when once placed in position. Laying was of the most primitive kind, and the bombard was packed up in its wood cradle to the required elevation once for all. When it was desired to breach a wall the bombard with its bed would be laid on the ground at about 100 yds. distance, the breech end of the gun or the rear end of the bed abutting against a solid baulk of wood fixed to the ground. "Mons Mcg" was originally provided with a wood cradle. It is by no means certain when wheeled carriages were introduced. They must have gradually appeared as a means of surmounting the difficulties engendered by the recoil of the piece and of transport of the early guns and their cradles. Andrea Redusio mentions in Chronicon Tarvisinum the use of two wheeled bombard carriages at the siege of Quero by the Venetians in 1376. It does not follow that these weapons were of large dimensions, as the term "bombard" was applied to small guns as well as to the more ponderous types. The ancient carriages used on land are remarkable from the fact that in general design they contain the main principles which have been included in field carriages up to the present day. Until 1870 the body of all field carriages was made of wood. In an early type the trail portion was made of a solid baulk of timber supported at the front by a hard wood axletree, on the arms of which the wheels were placed (iron axletrees were introduced by Gribeauval in 1765). The gun resting in its wooden cradle was carried in bearings on the trail immediately over the axletree (fig. 4), the cradle being provided with an From Clephan, Early Ordnance. FIG. 4.-Early Field Gun. axie or trunnions for the purpose. For giving elevation a wood arc was fixed to the trail towards the rear end, and the breech ead could be moved up and down along this arc and fixed at certain positions by a pin passing through both cradle and arc. About the middle of the 15th century the trunnions were formed with the gun-the wood cradle therefore became unnecessary and was discarded. The carriage was then formed of two strong cheeks or sides of wood fastened together by four wood transoms. At the front end the cheeks were secured to the wooden axletree, which was strengthened by a bar of iron let into its under side. Trunnion bearings were cut in the upper surface of the cheeks over the axletree, and these were lined with iron, while the trunnions were secured in position by iron cap-squares. Elevation was given by a wedge or "quoin" being placed under the breech and supported by a transom or stool bed. For transport the trail end of the carriage was supported on a limber, a pintle on the limber body passing through a hole in the trail. One set of shafts were fixed to the limber, and a single horse was harnessed to them; the remainder of the team were attached in pairs in front. A driver was provided for every two pairs of horses. In Italy oxen were often yoked to the larger guns instead of horses. Tartaglia mentions in his Now scientia (1562) that 28 oxen were required for a gun 15 ft in length and weighing 13,000 lb; horses were used for small guns only. For service on board ship the difficulties of the cramped situation seem to have been surmounted in an ingenious manner In the "Mary Rose," sunk in the reign of Henry VIII, the brass guns with trunnions were mounted on short wood carriages provided with four small wood wheels called "trucks" and fastened to the gun ports by rope breechings. The iron breechloading guns were employed in restricted positions where loading at the muzzle would be difficult. They had no trunnions and were mounted in a wood cradle, the under side of which was grooved to enable it to slide on a directing bar. At the end of the 17th century not much progress had been made. The larger guns were mounted on short wood carriages having two or four "trucks." The guns and carriages recoiled along the vessel's deck, and where this endangered the masts or other structures the recoil was hindered by soft substances being laid down in the path of the recoil. The small guns were mounted in iron Y pieces-the upper arms being provided with bearings for the gun trunnions-and the stalk formed a pivot which rested in a socket in the vessel's side or on a wall, so that the gun could be turned to any quarter. Similar carriages (fig. 5) existed until the advent FIG. 5.-Truck Carriage. of rifled guns, but a few small improvements, such as screw elevating gear in place of the quoin, had been approved. Cast iron standing carriages were also, about 1825, used on land for hot climates and situations not much exposed. Sighting. The earliest guns were not provided with sights or other means for directing them. This was not important, as the range seldom exceeded 100 yds. As, however, ranges became longer, some means became necessary for giving the correct line and elevation (see also SIGHTS). The direction for line was easily obtained by looking over the gun and moving the carriage trail to the right or left as was necessary. For elevation an instrument invented by Tartaglia called a Gunner's Quadrant (sometimes also called a Gunner's Square) was used; this was a graduated quadrant of a circle (fig. 6) connecting a long and FIG. 6.-Gunner's Quadrant. short arm forming a right angle; a line with a plummet hung from the angle in such a manner that on the long arm being placed along the bore near the muzzle the plummet hung down against the quadrant and indicated the degrees of elevation given to the piece. The quadrant was divided into 90° and also into 12 parts; it was continued past the short arm for some degrees to enable depression to be given to the gun. The instrument was also used for surveying in obtaining the heights of buildings, and is still much employed for elevating guns in its clinometer form, in which a level takes the place of the plummet. For short range firing a dispart sight was in use early in the 17th century. A notch was cut on the top of the breech or base ring, and on the muzzle ring a notched fore sight (called the dispart sight) was placed in the same vertical plane as the notch, and of such a height that a line stretched from the top of the breech ring notch to the notch of the foresight was parallel to the axis of the bore. These sights were well enough for close, horizontal fire and so long as the enemy were within what was called "point blank" range; that is the range to the first graze, on a horizontal plane, of the shot when fired from a gun the axis of which is horizontal. As this range depends entirely, other things being equal, on the height of the gun's axis above the horizontal plane, it is not very definite. When, however, the enemy were at a greater distance, elevation had to be given to the gun and, as a quadrant was slow and not easy to use, there was introduced an instrument, called a Gunner's Rule (see The Art of Gunnery, by Nathanael Nye, 1670), which was really a primitive form of tangent sight. This was a flat brass scale 12 or 14 in. long divided on its flat surface into divisions | muzzle owing to the position in which they were placed, and in proportional to the tangents of angles with a base equal to the order to obtain rapidity each gun was furnished with several distance from the notch on the base ring to the dispart notch. A chambers. slit was made along the rule, and a thread with a bead on it was Guns of this nature, called Petrieroes a Braza, were used in mounted on a slider so that it could be moved in the slit to any particular positions even at the end of the 17th century. Moreti required graduation. By sighting along the bead to the dispart states that they carried a stone ball of from 2 lb to 14 lb, which the gun could be laid on any object. Later still, the requisite elevation was obtained by cutting a series of notches on the side of the base ring and one on the muzzle ring. These were called "Quarter Sights" and allowed of elevations up to 3°; the lowest notch with the one on the muzzle swell gave a line parallel to the axis of the bore but above it so as to clear the cap-squares of the trunnions. This system was also used in bronze field guns and in all cast iron guns up to the 32-pdr. Difficulties in laying occurred unless the direction was obtained by looking over the top or dispart sight and the elevation then given by the quarter sights. This was the system of sighting in use during the great naval actions of the end of the 18th century and the beginning of the 19th century. A pointed dispart sight was often used, and for naval purposes it was fixed on the reinforce near the trunnions, as the recoil of the gun through the port would destroy it if fixed on the muzzle swell. The double sighting operation was rendered unnecessary by the use of "tangent scales" introduced by Gribeauval. Similar scales were soon adopted in the English land service artillery, but they were not fully adopted in the English navy until about 1854 (see Naval Gunnery, by Sir Howard Douglas, p. 390), although in the United States navy a system of sighting, which enabled the guns to be layed at any degree of elevation, had been applied as early as 1812. These tangent scales were of brass fitting into sockets on the breech end of the gun; they were used in conjunction with the dispart fore sight and gave elevation up to 4° or 5° over the top of the gun. For greater elevation a wooden tangent scale was provided which gave elevation up to 8° or 10°. In the British navy, before tangent sights were used, the plan often adopted for rapidly laying the guns was by sighting, with the notch on the breech ring and the dispart sight, on some part of the masts of the enemy's vessel at a height corresponding to the range. With sailing ships about the middle of the 19th century the angle of heel of the vessel when it was sailing on a wind was ascertained from the ship's pendulum, and the lee guns elevated or the weather guns depressed to compensate by means of a graduated wooden stave called a "heel scale" of which one end was placed on the deck or last step of the carriage whilst the upper end read in connection with a scale of degrees engraved on the flat end of the cascable. Subsequently the term "tangent sight" was given to the "tangent scales," and they were fitted into holes made in the body of the gun-the foresight usually being fitted to a hole in the gun near the trunnions. Two pairs of sights-one at each side-were generally arranged for, and in rifled guns the holes for the tangent sight bars were inclined to compensate for the drift of the projectile. As the drift angle varies with the muzzle velocity, the tangent sights of howitzers were set vertically, so that for the various charges used the deflection to compensate for drift had to be given on the head of the sight bar. Modern forms of sights are described and illustrated in the article SIGHTS. Breech-loading ordnance dates from about the end of the 14th century, or soon after the introduction of cannon into England (Brackenbury, Proc. R.A.I. v. 32). The Breech gun body, in some cases, was fixed to a wood loading Ordnance. cradle by iron straps and the breech portion kept in position between the muzzle portion and a vertical block of wood fixed to the end of the cradle, by a wedge. Accidents must have been common, and improvements were made by dropping the breech or chamber of the weapon into a receptacle, solidly forged on or fastened by lugs to the rear end of the gun (fig. 7) This system was used for small guns only, such as wall pieces, &c., which could not be easily loaded at the FIG. 7.-Early Breech-loader. was placed in the bore of the gun and kept in position by wads. The chambers, resembling an ordinary tankard in shape, had a spigot formed on their front end which entered into a corresponding recess at the rear end of the bore and so formed a rude joint. Each chamber was nearly filled with powder and the mouth closed by a wood stopper driven in; it was then inserted into the breech of the gun and secured by a wedge. Even with feeble gunpowder this means of securing the chamber does not commend itself, but as powder improved there was a greater probability of the breech end of the gun giving way; besides which the escape of the powder gas from the imperfect joint between the chamber and gun must have caused great inconvenience. To these causes must be attributed the general disuse of the breech-loading system during the 18th and first half of the 19th centuries. Robins mentions (Tracts of Gunnery, p. 337) that experimental breech-loading rifled pieces had been tried in 1745 in England to surmount the difficulty of loading from the muzzle. In these there was an opening made in the side of the breech which, after the loading had been completed, was closed by a screw. The breech arrangement (fig. 8) of the rifled gun in vented by Major Cavalli, a Sardinian officer, in 1845, was far superior to anything tried previously. After the projectile and charge had been loaded into the gun through the breech, a cast iron cylindrical plug, cupped on the front face, was introduced into the chamber; a copper ring was placed against its rear face; finally a strong iron wedge was passed through the body of the gun horizontally just in rear of the plug, and prevented it being blown out of the gun. In England the breech of one of the experimental guns was blown off after only a few rounds had been fired. In Wahrendorfi's gun, invented in 1846, the breech arrangement (fig. 9) was very similar in principle to the Cavalli gun. In addition to the breech plug and horizontal wedge there was an iron door, hinged to the breech face of the gun, which carried a rod attached to the rear of the breech plug. The horizontal wedge had a slot cut from its right side to the centre, so that it might freely pass this rod. After loading, |