Part 146

_To turn a_ SIEGE _into a blockade_, (_Convertir le Siege en blocus_, _Fr._) is to give over the attack, and endeavor to take it by famine; for which purpose all the avenues, gates, and streams, leading into the place, are so well guarded, that no succor can get in to its relief.

_To insult a work_, to attack it in a sudden and unexpected manner, with small arms, or sword in hand.

_Surprise_, is the taking a place by stratagem or treason.

_To escalade a place_, is to approach it secretly, then to place ladders against the wall, or rampart, for the troops to mount and get into it that way.

_To petard a place_, is privately to approach the gate and fix a petard to it, so as to break it open for the troops to enter.

_Line of circumvallation_, is a kind of fortification, consisting of a parapet, or breast-work, and a ditch before it, to cover the besiegers against any attempt of the enemy in the field.

_Line of countervallation_, is a breast-work, with a ditch before it, to cover the besiegers against any sally from the garrison, in the same manner that the line of circumvallation serves to protect them in the field.

_Lines_, are works made to cover an army, so as to command a part of the country, with a breast-work and a ditch before it.

_Retrenchment_, a work made round the camp of an army, to cover it against any surprise.

_Line of counter-approach_, a trench which the besieged make from the covert-way to the right and left of the besiegers attacks, in order to scour their works. This line must be perfectly enfiladed from the covert-way and the half-moon, &c. that it may be of no service to the enemy, in case he gets possession of it.

_Batteries_ at a _siege_, cannot be erected till the trench is advanced within reach of the cannon of the place; that is, within what is generally understood to be a point-blank range, which is reckoned about 300 toises, or 1800 feet.

_Cannon_ is made use of at a _siege_ for two different purposes; the first to drive away the enemy from their defences; and the second, to dismount their guns. To produce these two effects, the batteries should not be above the mean reach of cannon-shot from the place: therefore there is no possibility of constructing them, till the first parallel is formed; and as the distance of the first parallel from the second is generally 300 toises, the batteries must be on this line, or beyond it, nearer the town.

The construction of batteries belongs to the officers of the royal artillery, who generally consult with the engineer that has the direction of the siege, as well about their situation as about the number of their guns and mortars. They must be parallel to the works of the town which they are to batter. It is customary to place the mortar-batteries and gun-batteries side by side, and in the same line, to the end that they may batter the same parts. The use of both is to demolish the enemy’s works, to dismount their guns, to penetrate into their powder magazines, and to drive the besieged from their works and defences; as also to ruin and destroy the principal buildings, by setting fire to the town; and to fatigue and distress the inhabitants in such a manner, that they shall press the garrison to surrender.

_To sally at a siege_, is to go privately out of a besieged town, fall suddenly upon the besiegers, and destroy part of their works, spike their cannon, and do every other possible damage.

_A sally_, a secret movement which is made out of a besieged town or place, by a chosen body of troops, for the purpose of destroying an enemy’s out-works, &c. Sallies are seldom made when the garrison is weak; for although they molest the enemy, and keep him on the alert, yet the chance of losing men renders it prudent to keep within the works.

_Saps_ in a _siege_, are trenches made under cover from the fire of the place, behind a mantlet or stuffed gabion: they are generally ten or twelve feet broad.--This work differs from the trenches, in as much as the latter are made uncovered. The sap has also less breadth; but when it is as wide as the trench, it bears the same name. There are various sorts of saps, viz.

_Single sap_, is that which is made on one side only, or, which is the same thing, has only one parapet.

_Double Sap_, has a parapet on each side, and is carried on wherever its two sides are seen from the place.

_Flying sap_, is that in which the besiegers do not give themselves the trouble of filling the gabions with earth: it is made where the workmen are not much exposed, and in order to accelerate the approaches.

_Sap-faggots_, are a kind of fascines, but only three feet long, and about six inches in diameter.

_Saucissons_, are another species of fascines, from 12 to 19 feet long, and from 8 to 10 inches in diameter, and are used in making batteries, and repairing the breaches.

_Sortie._ See SALLY.

_Tail_, or _rear of the trench_, (_Queue de la tranche_, _Fr._) is the first work the besiegers make when they open the trenches.

_Tambour_, is a kind of traverse, at the upper end of the trench or opening made in the glacis to communicate with the arrows. This work hinders the besiegers from being masters of the arrow, or discovering the inside of the place of arms belonging to the covert-way.

_Traverse_, in a _siege_, a kind of retrenchment which is made in the dry ditch, to defend the passage over it.

_Trenches_, are passages or turnings dug in the earth, in order to approach a place without being seen from its defences.

_Wool-packs_, used in a _siege_, differ from sand-bags, in this only, that they are much larger, and, instead of earth, they are filled with wool. They are used in making lodgments in places where there is but little earth, and for other similar purposes. They are about five feet high, and 15 inches in diameter.

_Rear of an attack_, is the place where the attack begins.

_Front, or head of an attack_, that part next to the place.

_Mantlets_, are wooden fences, rolling upon wheels, of two feet diameter; the body of the axle-tree is about four or five inches square, and four or five feet long; to which is fixed a pole of eight or ten feet long, by two spars; upon the axle-tree is fixed a wooden parapet, three feet high made of three-inch planks, and four feet long, joined with dowel-pins, and two cross-bars: this parapet leans somewhat towards the pole, and is supported by a brace, one end of which is fixed to the pole, and the other to the upper part of the parapet. Mantlets are used to cover the sappers in front against musquet shot.

_Maxims in_ SIEGES are, 1st. The approaches should be made without being seen from the town, either directly, obliquely, or in the flank.

2. No more works should be made than are necessary for approaching the place without being seen; _i. e._ the besiegers should carry on their approaches the shortest way possible, consistent with being covered against the enemy’s fire.

3. All the parts of the trenches should mutually support each other; and those which are farthest advanced, should be distant from those that defend them above 120 or 130 toises, that is, within musquet shot.

4. The parallels, or places of arms the most distant from the town, should have a greater extent than those which are the nearest, that the besiegers may be able to take the enemy in flank, should he resolve to attack the nearest parallels.

5. The trench should be opened or begun as near as possible to the place, without exposing the troops too much, in order to accelerate and diminish the operations of the siege.

6. Care should be taken to join the attacks; that is, they should have communications, to the end that they may be able to support each other.

7. Never to advance a work, unless it be well supported; and for this reason, in the interval between the 2d and 3d place of arms, the besiegers should make, on both sides of the trenches, smaller places of arms, extending 40 or 50 toises in length, parallel to the others, and constructed in the same manner, which will serve to lodge the soldiers in, who are to protect the works designed to reach the third place of arms.

8. Take care to place the batteries of cannon in the continuation of the faces of the parts attacked, in order to silence their fire; and to the end that the approaches, being protected, may advance with great safety and expedition.

9. For this reason the besiegers shall always embrace the whole front attacked, in order to have as much space as is requisite to place the batteries on the produced faces of the works attacked.

10. Do not begin the attack with works that lie close to one another, or with rentrant angles, which would expose the attack to the cross fire of the enemy.

_Stores required for a month’s_ SIEGE _are as follows_:

Powder, as the garrison is more or less strong 8 or 900,000 lb. Shot{for battering pieces 6000 {of a lesser sort 20,000 Battering cannon 80 Cannons of a lesser sort 40 Small field-pieces for defending the lines 20 Mortars for throwing{shells 24 {stones 12 Shells for mortars 15 or 16,000 Hand-grenades 40,000 Leaden bullets 180,000 Matches in braces 10,000 Flints for musquets, best sort 100,000 Platforms complete for guns 100 Platforms for mortars 60 {carriages for guns 60 Spare{mortar-beds 60 {spunges, rammers, and ladles, in sets 20 Tools to work in trenches 40,000

Several hand-jacks, gins, sling-carts, travelling forges, and other engines proper to raise and carry heavy burdens; spare timber, and all sorts of miner’s tools, mantlets, stuffed gabions, fascines, pickets, and gabions.

SIENS, _Fr._ The plural of sien, _his_, _her’s_ or _one’s_ own. This word is used among the French, to signify the same as _gens_, men, people, soldiers; viz. _ce général fut abandonné par les siens_. That general was abandoned by his own soldiers.

SIEVE, an instrument, which by means of hair, lawn, or wire, is capable of separating the fine from the coarse parts of any powder. See GUNPOWDER, LABORATORY, &c.

SIFFLEMENT, _Fr._ Literally means the noise of a whistle. It is used to express the sound which a ball or bullet makes when it cuts the air; as _sifflement des armes à feu_. The whistling or whizzing noise of fire arms.

SIES or SHIAS, _Ind._ A tribe of people in the N. West of India.

SIFFLET, _Fr._ A whistle. The French make use of the whistle on board their ships in the same manner as we do. It answers the same purpose at sea, that the drum and trumpet do on shore. The boatswain’s whistle pipes all hands up, as occasion requires in a ship: and the drum and trumpet collect troops together, in camp, garrison, or elsewhere.

SIG, an old Saxon word, importing victory.

SIGHT, (_La Mire_, _Fr._) a small piece of brass or iron which is fixed near to the muzzle of a musquet or pistol, to serve as a point of direction, and to assist the eye in levelling.

SIGN, a sensible mark or character, denoting something absent or invisible. As the trace of a foot, the hand-writing or mark of a man; also the subscription of one’s name.

SIGN _Manual_. The king’s signature is so called. All commissions in the regular army of Great Britain, army warrants, &c. bear the sign manual. The appointments of officers in the volunteers have been so distinguished during the present war. Adjutants only in the militia have their commissions signed by the king; those of the field officers, captains, and subalterns, &c. are signed by the lords lieutenants of counties, or by their deputies for the time being, sanctioned by a previous intimation from the secretary of state, that the king does not disapprove of the names which have been laid before him.

SIGNAL, (_Signal_, _Fr._) Any sign made by sea or land, for sailing, marching, fighting, &c. Signals are likewise given by the short and long rolls of the drum, during the exercise of a battalion.

SIGNAL, in the _art of war_, a certain sign agreed upon for the conveying intelligence, where the voice cannot reach. _Signals_ are frequently given for the beginning of a battle, or an attack, usually with drums and trumpets, and sometimes with sky-rockets, &c.

SIGNAL _of attack or assault_, _(Signal d’une attaque, ou d’un assaut_, _Fr._) This signal may be given in various ways. By the discharge of a lighted shell, by sky-rockets, by colors displayed from a conspicuous spot, &c. In 1747 marshal Lowendal made use of lighted shells or bombs, when he laid siege to the town of Bergen-op-zoom. During the consternation of the inhabitants, which was excited by a continual discharge of these signal shells, the grenadiers entered a practicable breach, and took the town by storm.

SIGNAL-_flags_ in _ancient military history_, was a gilded shield hung out of the admiral’s gallery; it was sometimes a red garment or banner. During the elevation of this the fight continues, and by its depression or inclination towards the right or left, the rest of the ships were directed how to attack their enemies, or retreat from them.

SIGNALS _made by the colors of an army_, (_Signaux des enseignes_, _Fr._) The ancients had recourse to all the various methods which could be used by signals, to express the particular situation of affairs, and to indicate measures that should be adopted. If, during an engagement, victory seemed inclined more to one side than another, the colors belonging to the victorious party were instantly bent towards its yielding antagonist. This signal was conspicuous to the men, and excited them to fresh efforts. They imbibed the most lively hopes of success, and eagerly pressed forward to reap the advantages of bravery and good conduct.

When an army was hard pressed by its enemy, the colors of the former were raised high in the air, and were kept in a perpetual flutter and agitation, for the purpose of conveying to the soldiers, that the issue of the battle was still doubtful, and that nothing but courage and perseverance could determine the victory. If, in the heat of action, any particular regiment seemed to waver and give way, so as to cause an apprehension that it might finally be broken, its colors were instantly snatched out of the bearer’s hands by the general or commanding officer, and thrown into the thickest of the enemy. It frequently happened that the men who were upon the point of yielding ground and flying, received a fresh impulse from this act, rallied, and by a desperate effort of courage recovered the colors, and restored the day. This method of re-animating their legions was generally resorted to by the Romans. We have had instances in modern times, where the fortune of the day has been wholly decided by some sudden and unexpected act of an individual. In the reign of Louis XIV. a private soldier threw his hat into the midst of the enemy during a hard fought and doubtful battle, expressing thereby that fresh succours were arrived to strengthen the French army. This circumstance, so apparently trifling, produced the desired effect. It threw the enemy into confusion, gave the French fresh spirits, and finally determined the victory in their favor. We read of various instances in which signals have been used to express the personal danger of a king or general, who was fighting at the head of a select body of men. The knowlege of the critical position in which their leader stood, excited fresh courage in the rest of the troops, and drove them to acts of the greatest intrepidity. In the course of the present war some examples of the same sort might be adduced, both on the side of Austria, and on that of France. The bridge of Lodi, the passage of the Tagliamento, &c. would illustrate any observations we could make upon the subject.

Nor are the advantages which arise from the use of signals confined to these particular cases. Various circumstances grow out of the desultory nature of military operations, to render flags of communication indispensibly necessary. The vast scope which is given to modern tactics, makes it impossible that the human eye or voice should take in all the critical manœuvres or evolutions which occur, when an extended line is actually engaged. The right wing may be giving way while the left is gaining ground, and the centre might be in danger while the two flanks were rapidly advancing with apparent security against the enemy. Under these circumstances a general, by means of communicating signals, might be enabled to provide for every contingency, without losing time by sending his orders verbally. Although signal flags, in modern engagements, have been generally laid aside, their use has been acknowleged in the adoption of warlike instruments, which, by the variety of their sounds, convey the necessary directions to an engaging army.

The ancients had signals which they called _mute signals_, (_signaux muets_.) These consisted in certain actions or signs that were made by a general; such as waving the hand, brandishing a stick or sword, or by exhibiting to view any part of his dress, accoutrements, &c. Instances of the same kind have occurred among the moderns. Under this denomination may likewise be classed the different signals which are made for the movement, marching, and manœuvring of troops in and out of quarters. When troops are scattered or separated from one another, it is usual to communicate by means of fires lighted upon eminences during the night, and by smoke during the day.

In former times large pieces of wood were hung above the towers of cities or castles, which, by being drawn up or lowered, gave intelligence of what passed. This method has been succeeded by the invention of telegraphs, which answer every purpose of communication, when they can be established through an extent of country. At the battle of Fleurus, the French employed balloons, to which cords were attached, able officers elevated in the air sent down, by the cords, an account of the movements of the Austrians, a signal thus conveyed enabled Jourdan to direct a tremendous battalion fire, and a heavy charge of cavalry, by which the battle was decided. Besides those signals, there are others which may be called _vocal_ and _demi-vocal_. The vocal signals are those of the human voice, which consist in the necessary precautions that are adopted to prevent a guard or post from being surprised, to enounce words of command in action, &c. Of the first description are paroles and countersigns, which are exchanged between those to whom they are intrusted, and which are frequently altered, during the day and night, to prevent the enemy from receiving any information by means of spies. The demi-vocal signals are conveyed by military instruments; the different soundings of which indicate, instantaneously, whether an army is to halt or to advance, whether troops are to continue in the pursuit of an enemy, or to retreat.

The demi-vocal signals, directed to be observed in the British service, as far as regards the manœuvring of corps, &c. consist of signals for the government of light infantry, and of cavalry regiments, squadrons, or troops: the latter are properly called soundings. Rifle or light infantry signals are to give notice--to _advance_; to _retreat_; to _halt_; to _cease_ firing; to _assemble_, or call in all parties. Those signals should be always considered as fixed and determined ones, and are never to be changed. The bugle horn of each company should make himself perfect master of them. All signals are to be repeated; and all those signals which are made from the line or column, are to convey the intention of the commanding officer of the line to the officer commanding the light infantry, who will communicate them to the several companies or detachments either by word or signal.

SIGNAL-_staff_. In matters of military parade it is usual to fix a flag, somewhat larger than a camp color, to point out the spot where the general or officer commanding takes his station in front or a line. This is called the signal staff.

SIGURGHAL, _Ind._ A feudal tenure.

SIGUETTE, _Fr._ The same as cavesson, a sort of noseband, sometimes made of iron, and sometimes of leather, or wood; sometimes flat, and sometimes hollow or twisted; which is put upon the nose of a horse, to forward the suppling and breaking of him.

SILENCE, (_Silence_, _Fr._) This word is used by the French as a caution to soldiers to prepare for any part of the military duty or exercise. The French have likewise another term which corresponds with our word attention. See GARDE. We use _Attention_ in both instances.

SILHATARIS, _Fr._ See SPAHIS.

SILLAGE, _Fr._ The wake of a ship; the trace which a vessel leaves astern when she moves forward.

SILLON, in _fortification_, is a work raised in the middle of a ditch, to defend it when it is too wide. It has no particular form, and is sometimes made with little bastions, half-moons, and redans, which are lower than the works of the place, but higher than the covert way. It is more frequently called _envelope_, which see.

SIMILAR _polygons_, are such as have their angles severally equal, and the sides about those angles proportional.

_To_ SIMPLIFY. This word has been adopted amongst men of business and arrangement, from the French _simplifier_, which means to relate the bare matter of fact. This signification likewise reaches every species of analysis, &c. Thus the advantage of the new manual over the old, is owing to the reduction of the latter into fewer motions and words of command, by which that exercise has been considerably simplified. The oblique facings, under the denomination of _quarter facings_, _half facings_, of single files; the half wheelings, quarter wheelings, and half quarter wheelings of sections, platoons, divisions, and battalions, are all more simple in the new discipline than the methods of the old.

SINE. In geometry, a right _sine_, is a right line drawn from one end of an arch perpendicularly upon the diameter drawn from the other end of the arch.

SINES. See table of _Natural Sines_, at the end of the word GUNNERY.

SINGE, _Fr._ An instrument so called. See PENTAGRAPH.

SINGLE _combat_, a contest in which not more than _two_ are engaged.

SINUS, _Fr._ See LINE for its geometrical acceptation.

SINUS, in English, signifies a bay of the sea, an opening of the land; any fold or opening.

SINUSOIDE, _Fr._ A geometrical curve, which has been imagined by Monsieur Belidor, for the purpose of balancing or preserving the equipoise of a drawbridge. See _Science des Ingénieurs_, liv. iv. See likewise the specific construction of this curve as explained by the marquis de l’Hopital, in a book intitled, _Acta Eruditorum_, published at Leipsic in 1695; and demonstrated by M. Bernouilli, who discovered that this curve was nothing more than the epicycloid, which see.

SIPHON, (_Syphon_, likewise _Ciphon_, _Fr._) In hydraulics, a crooked tube, one leg or branch whereof is longer than the other. It is used in the raising of fluids, emptying of vessels, and in various hydrostatical experiments.

SIRKAR, _Ind._ The government.

SIROC. From Sirius, the dog-star. The wind, which we call south-east, is so called in Italy.