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English engineer, first taught the French the art of throwing shells, in 1634. Red hot balls were thrown from mortars, at the siege of Stralsund in 1675; and since that time they have frequently been employed.

MUSKET. The length of the musket is fixed to three feet eight inches, from the muzzle to the touch-pan, and its bore is such as may receive a ball of sixteen to the pound. There are two sorts of firing with muskets, offensive and defensive. 1. Offensive. The object of fire against cavalry is to keep them at a distance, and to deter them from the attack. But against infantıy, it cannot be too heavy or quick, and should be continued till the enemy is beaten or repulsed. 2. Defensive fire belongs principally to infantry, when posted on heights, which are io be defended by musketry. As soldiers generally present too high, and as fire is the greatest consequence to troops that are on the defensive, the habitual mode of firing should therefore be rather at a low level than a high one.

ORDNANCE is a general term for all sorts of great guns or cannon, mortars, &c. Ordnance, in England, is distinguished into two kinds, viz. field-pieces, which are from the smallest to twelve pounders, and cannons of a battery, which are from a culverin to a long gun. The Board of Ordnance was instituted before the year 1548, in which year Sir Philip Hoby was styled Master of the Ordnance. The board now consists of a master-general, a lieutenantgeneral, surveyor-general, clerk of the ordnance, &c. and it deliberates, determines, regulates, and orders, every thing relating to the artillery and garrisons. By courtesy, the master-general can, of himself, do much of the business of the board.

Pistol. This is generally carried at the saddle-bow, by horse soldiers.

Poinard, a dagger or short sword, used chiefly by foreign nations."

Shor, includes all sorts of balls, or bullets for fire-arms, from the cannon to the pistol. Those for cannon are generally of iron, but for muskets, carbines, and pistols, are of lead. Shot, for fowling, is called hail, on account of its figure and size. The lead being melted, stirred, and skimmed, a quantity of powdered yellow orpiment is strewed

in it, as much as will lie on a shilling to 12 or 15lbs. of lead. The whole being well stirred, the orpiment becomes ignited. This done, a copper plate, hollow in the middle and three inches in diameter, bored through with 30 or 40 small holes, according to the size of the shot, is placed on an iron frame over a tub of water, four inches above the water: the hollow part being very thin. On this plate are laid burning coals, to keep the melted lead in a state of fusion, The lead is poured .gently with a ladle on the middle of the plate, and makes its way through the bottom of the plate into the water, in round drops. Great care is taken to keep the lead on the plate in a proper degree of heat; if too cold, it will stop the holes, and if too hot, the drops will crack and fly. The shot, thus made, are dried

a gentle fire, being stirred to prevent their melting; when dry, the greater are separated from the smaller, by passing them through sieves.

over

§ 4. Telegraphs.

1. The telegraph, though brought into general use only by the circumstances arising from the French Revolution, is of great antiquity, and the principle appears to have been known from the earliest ages, as the ancient Greeks, used signals to convey information to their distant friends. There is

very little doubt that the intelligence of the burning of Troy was conveyed to Greece by means of tetegraphic signals, as the event was known in that country very soon after it had happened. The Chinese, when they send couriers on the great canal, or when any great man travels there, make signals by fire, from one day's journey to another, to have every thing prepared. Most barbarous nations used, formerly, to give the alarm of war, by fires lighted on the hills, or rising grounds. Various modes have been adopted for communicating intelligence by signals for every letter in the alphabet, which are observed by telescopes, and repeated at the respective stations. Both day and night telegraphs have been proposed by different writers, and others have insisted on the adoption of a vocabulary in which every sign should represent a word, instead of a single letter as now practised.

2. The telegraph, set up by government in a chain of

stations from the admiralty to the sea-coast, consists of six octagonal boards; each of which is poised upon an axis in a frame. And this is done in such a manner, that the board can be either placed vertically, so as to appear with its full size to the observer at the nearest station, or it becomes invisible to him, by being placed horizontally, so that the narrow edge alone is exposed, which edge is invisible from a distance. These six boards make thirty-sir changes by the most plain and simple mode of working; and will make many more, if more were necessary. By a change in the position of one of these octagonal boards, any letter may be made, and in certain positions, a variety of things may be signified, according to the will of the persons at the two extreme posts, employed in making the signals. Thus one board being in an horizontal position, and the others shut, or in a perpendicular situation, may denote the letter a; two only being in an horizontal position may give the letter b; three in the same manner the letter c, and so on. As there may be made as many changes with these boards, as with the same number of bells, the letters of the alphabet may be made with ease, and a sufficient number of signals may be formed for extraordinary purposes.

3. Two attempts to render the telegraph useful in the fiehl, have been made by Mr. KNIGHT SPENCER, SECRETARY TO THE SURRY INSTITUTION.

(1.) The Anthropo- Telegraph, which consists of two circular disks made of basket-work, about eighteen inches in diameter, painted white, with a black ball in the centre of each. These are held by the person to make the signals, one in each hand. By displaying one or both, according to the signal intended at different angles; all necessary information, orders, and commands, may be conveyed by the commanders of armies to every part of their line, &c. This invention was rewarded by the Society for the Encouragement of Arts, Manufactures, and Commerce, with their silver medal, and is described at length in their Transactions for 1809, vol. xxvii. p. 153.

(2.) The Cump- Telegraph, (described in the Philosophical Magazine of November, 1810) consists, for day signals, of three flexible balls mounted on staves about 10 or 12 feet in height; one of which is distinguished by being

double, and is used as a centre point; the other two are carried to different distances, to the right or left of the centre point, according to the sig al intended. This invention is extremely simple, portable, and very powerful, the whole apparatus not being more cumbrous than three halberts, or pikes. Questions have been asked by it, and answers obtained, frequently, at the distance of six miles within the space of three minutes. But the most important part of the invention is, that by which night signals are made. It consists of lights, or lanthorns, constructed with hollow lenses, filled with different coloured fluids, the effects of which are such, that communications both on shore and afloat, may be made, with inore certainty, than any hitherto made by day.

LIEUTENANT SPRATT, of the Royal Navy, obtained in 1809, from the Society of Arts, &c. their silver medal for his invention of the homograph, or a method of making signals by sea or land, by means.of a white pocket-handkerchief held in different positions with the body. It is described at length in the Transactions of the Society, vol. xxvii. p. 163.

There have been various other telegraphs invented by Dr. Hooke, Mr. Garnett, Captain Pasley, &c. but the above will suffice to develope the main principle.

Select Books on Fortification, and Military Tactics.

Muller's Fortification, Muller's Artillery, Robins' Gunnery, Euler's do. by Brown), Pleydell's Fortification, Icchee's Field Fortification ; all except Euler in svo. James' Military Dictionary, 2 vols. 8vo. Ady's Pocket Gunner, 12mo. Muller's Elements of the Science of War, 3 vols. 8vo. Essays on the Art of War, 2 vols. 8vo. Military Mentor,

2 vols. 8vo.

SECT. VI.NAVIGATION AND NAVAL TACTICS.

1. Navigation was formerly very dangerous, and much more laborious than it is at present. Persons did not dare to venture far out into the open sea, but coasted along without losing sight of the shore. But since the invention of the compass they cross the seas with more contidence and safety. Before this valuable discovery, it was a sort of wonder to make even short sea voyages. In Homer's time it required great preparations and long deliberation before his heroes could determine to cross the Egean Sea. The expedition of Jason and his Argonauts to the island of Colchis, was considered as the wonder of the world. But what are these in comparison of our sea voyages ? By the invention of the compass we are enabled to make long voyages: the magnetic needle, turning always towards the north, informs the navigator in what direction to steer the ship, in order to arrive at his destined port. In the darkest night, in the most cloudy days, in the very midst of the ocean, this instrument serves him as a guide, and leads him to the remotest part of the earth.

2. Navigation, contemplated as a branch of science, includes the principles of mechanics, of plane and spherical trigonometry, and of astronomy. The usual classification is, into plane, current, parallel, middle latitude, and Mercator's sailing. The mechanical operations determine the setting of currents, and the velocity and direction of the ship, by the log and compass; the astronomical observations serve for the determination of the latitude and longitude: and the various computations furnish some of the finest applications of mathematical science.

3. In general, we consider navigation only in reference to the advantages which it affords us, but we should also consider the construction and motion of ships, without which navigation could not exist: of which the former is designated by the term ship-building, the latter by that of seamanship ; both requiring the union of great scientific knowledge and great practical skill. The weight of a ship is greater than we imagine; and it requires but little attention to be convinced that the pressure on the water must be prodigious. A man of war which carries 800 men, has commonly provisions laid in to support that number for three months, and carries besides from 70 to 100 guns. Now supposing each man to weigh only 100 pounds, and each cannon 900, (although there are cannons that weigh more than 40 hundred;) and supposing that each man * eats but three pounds weight of food in the day, this moderate calculation will make the burthen amount to more than 386,000 pounds.. But the weight of the vessel itself is not taken into this calculation; the rigging, and a multitude of materials necessary to keep the vessel in repair, load the cannon, &c. are articles which at least equal, if

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