'From this, together with what has been said respecting the descent of balls, we know, and that is enough for our present purpose, that the terminal velocity of the cube must be much less than 185 feet per second; and consequently its effect or momentum inferior to that of a 3-08 ounce ball. The motion of a cubical shot will, besides, be quite irregular, descending sometimes with an angle, then a face, then an edge foremost, tumbling over and over in oblique, irregular directions, without any certainty, excepting that the velocity and effect will be much less than those of a round shot of equal weight.'

Our author smiles at the preference of the French writer for cross bows and ancient weapons of attack and defence; and compares the far shorter time in which Calais, Tournai, Thouars, Naples, &c., have fallen before firearms. He contends that sieges became uniformly shorter as gunnery was improved. Upon the main topic of this writer, he adds, "I give the results of some very careful experiments, made purposely to ascertain the precise effects of those natures of vertical fire, which M. Carnot proposes to adopt as the principal means of defence.'

Experiments with different charges of stones from

a ten-inch iron mortar. Elevation 45°.

1. Charge 10 oz. of powder, and fifty flint stones, each about 14 oz. The average range was 107 yards; but most of the stones were blown to pieces.

2. Charge 12 oz. of powder, and forty stones of hard granite of about 1 lb. each. The nearest stones fell at forty, and the furthest at 120 yards; the transverse spread was thirty yards.

3. Charge 16 oz. of powder, and forty-six stones, as before. The nearest stones fell at fifty, and the furthest at 130 yards from the mortar: the spread was forty-five yards. One stone went off to the right in an angle of about Forty-five degrees, and fell at the distance of 100 yards in that direction, very near a spectator placed, as he thought, in perfect safety.

Experiments with a brass pierrier. Diameter

sixteen inches. Elevation 45°.

1. Charge 24 lbs. of powder (which filled the chamber), and 100 granite stones of 1lb. each, piled up to the mouth of the pierrier in a basket with a bottom of wood. The nearest effect was twenty-eight yards; the furthest 300: the spread was seventy yards. Many of the stones broke.

2. Charge 14 lb. of powder, and seventy-five granite stones of 14 lb. each. The nearest effect was twelve yards, and the furthest 180. The spread was fifty yards.

In both cases it could not well be ascertained where the greatest effect was, on account of the great dispersion of the stones, many of which broke even with the reduced charge.

Applying these experiments to the new defences of M. Carnot, Sir Howard found that the nearest effect would take place in the gorge of the bastion; and that the furthest effect, P, plate I., would not reach the crest of the glacis, even with the full charge of powder. It appears, therefore, says he, that neither the third parallel,

VOL. IX

nor the couronnement of the glacis, are within the reach of stones forced to the utmost, from pierriers in the casemated battery; and the horizontal area of all those parts of the attack which come within its influence is so small, compared with the vast magnitude of the oval surface upon which the stones fall, that, it may be relied upon, not one stone in 1000 would take effect upon the besiegers.

A substitution of large balls and grenades, adds this writer, fired from mortars, would be less uncertain and more formidable; but even with these the dispersion is very great. 100 iron balls, of one pound each, were discharged from a ten-inch iron mortar, at forty-five degrees elevation, with a charge of 1 lb. 4 oz. of powder. The spread was fifty yards; the nearest effect 150, and the furthest 210 yards: the longitudinal dispersion was therefore sixty yards, and consequently the area of the surface affected by the descent of the balls, supposing it to be an ellipse whose axes are sixty and fifty yards, was 20,476 square feet. The chances of hitting would therefore be very remote, whilst the expenditure of iron would be immense. At the rate of discharge which M. Carnot mentions, page 231, it would require a provision of nearly 1,500,000 lbs. of iron for the seven casemates of one batterie de gorge.

"In regard to the display of vigor and resolution in personal conflict, which M. Carnot seems to think comparatively deficient in modern defences, it is clear,' says the above writer,' that the invention of gunpowder has narrowed the opportunities of displaying those qualities in the opera tions of a siege, properly conducted, more than in any other military enterprise. There is no opportunity for personal conflict, excepting in sorties, which, we have already shown, prove too frequently but a waste of life and valor, and in the defence of breaches, where also there is that to encounter which the ancients were not exposed to. M. Carnot's object in quoting so many sieges, is, to show that the defence of places by 'armes blanches' has constantly been more brilliant, more efficacious, of longer duration than by armes à feu. What, he says (p. 239), has the invention of powder, or the new process of attack, to do with the vigor and resolution that were used by the ancients? These, he observes, may alter the means but not the principles of resistance.

'Now here we differ from M. Carnot; and to close properly with this assertion, we have, rather fully, compared the ancient with the modern means of attack, for the purpose of showing that the general principles as well as means of defence are altered, and that both are inferior to those of attack when directed by scientific intelligence, and furnished with sufficient means. What can personal vigor and resolution do against the establishment of the ricochet batteries, and all the process of attack, until it come near enough to be checked by sorties? The defence by armes blanches' can only be applied to the defence of a breach; but a breach may always be made, whatever be the vigor, resolution, or strength of the garrison. The only means to oppose and retard the opening of a breach are by a powerful fire of artillery in the

2 H

6

first instance, then by counter-mines, and oc- and any other destructive missile that can be casionally by sorties. These may, at a great procured; and that a deep trench, previously sacrifice, retard the operation, but cannot alto- dug and filled with tarred faggots, and other gether defeat it. Do not these alter the princi- combustible materials, should be set on fire when ples as well as the means of defence? The the storming party is about to mount the breach. sieges of the ancients gave occasion for a great He also recommends (p. 297) cuts to be made many personal conflicts from the beginning into the parapet, on the flanks of the breach, of the enterprise; and so did modern sieges, from which the besieged can either fire, or drop until parallels or places of arms were ap- shells upon the assailants;-an expedient which, plied to protect the approaches and repel sor- after the breach is carried, will prevent the enemy ties but there is now no such field for personal from extending himself, by sapping in the parapet, prowess, and a place may certainly be breached, towards the shoulders and gorge of the bastion and exposed to the consequences of an assault, to the attack of the retrenchments. But, whatwithout giving the besieged any favorable op- ever obstacles and expedients be applied to close portunity of displaying personal exertion with the breach, they will inevitably be destroyed, 'armes blanches.' The operations of a siege, broken, or deranged by the heavy fire from the to this period, are chiefly what the French call breaching batteries established on the crest of par industrie,' which, instead of being secon- the glacis, which is always the immediate predary, as M. Carnot says, to the objects of per- lude to an assault. Consequently little reliance sonal valor, are the means which introduce the should be placed on any other means than the display of it; and we cannot see that his reason- personal valor and determination of the troops ing can attach to any thing but the defence of a actually placed behind these obstacles, who breach. With this also gunpowder has, or at should there use the most determined, devoted least ought to have, a great deal to do; for the exertions to prevent the enemy from gaining a guns that made the breach, can render it practi- footing on the breach. According to M. Carcable; they can prevent the besieged from closing not's method of opposing an assault, a footing it by exterior obstacles, and the interior defences might be gained, and a lodgment partly formed, may be molested by shells, stones, &c. M. before the corps d'élite could be drawn out from Carnot applies personal valor and determination their cover, and march forth to balayer' the less, in the first instance, to the defence of a rampart; and when once a footing is obtained, breach than we should do. He proposes (p. or a lodgment made, it is not easily recovered, 333, 4to. edition) to have fifteen or twenty pier- if proper measures have been taken to support riers blindés' ranged round the breach as a focus, the assault; and the attempt is always very and to keep near them, also under cover, a corps bloody and seldom successful. d'élite ready to march forth. When the besieger's troops put themselves in motion, to advance to the assault, M. Carnot recommends that the troops should be withdrawn from the rampart, in order to allow the stone-mortars to act. It is evident, he observes, that the enemy either will not arrive, or if he does, that it will be in disorder, after immense loss from the fire of the stone-mortars; upon which the fire should suddenly cease, the corps d'élite march forth, charge the enemy, and will very soon sweep them from the field of battle, whilst a good sortie will take them in flank and rear, destroy their epaulement,' &c. This is indeed a sweeping clause in M. Carnot's theory, and there needs no comment to show that it is the most fallacious part of his doctrine. The way to oppose an assault is undoubtedly to render the breach as inaccessible as possible, by every obstacle that can be applied, and to hurl upon the storming party quantities of stones, live-shells, grenades, combustibles, &c.; and some of the expedients proposed by M. Carnot for these purposes, and practised by the French in the Peninsula, are among the best parts of his elaborate treatise. He recommends, p. 310, that the breach should be strewed with crow's feet, harrows, chevauxde-frise, &c.; and that when the assault is about to be made, or expected to take place, the besieged should form a barrier on the summit of the breach, of strong six-pointed crow's feet, made of wood armed with iron points, firmly fastened to each other: that when the storming party advances to the assault, they should be assailed with a prodigious quantity of combustibles

'M. Carnot inserts a long quotation from the Sieur Antoine de Ville's Ingénieur parfait, published in 1629, which, he says, only requires some modifications which follow from the improvements that have been made in fire-arins since the period in which this work was written. This passage commences in the original (book iii. part ii. p. 372) with an enunciation (which M. Carnot suppresses, as he does several other parts of the passage), which shows how completely the author's directions must be considered, as indeed they are, obsolete. In proportion,' says M. de Ville, as the enemy make a breach, the besieged should endeavour during the following night to undo his work, restore, and throw it up again.' Whoever reads this passage in the original will perceive that very little of it can apply at all to the defence of a breach made by a battery established on the crest of the glacis, in a face which has been ricoched from the commencement of the siege, and whose acting flank is directly counter-battered, and also enfiladed from the third parallel. It were madness indeed to attempt to defend a breach made in this regular way, unless the besieged have a retrenchment. M. Carnot may adduce, and my readers may recur to, the sieges made in the Peninsula, in opposition to this assertion; but we have the public authority of a very distinguished British engineer (lieutenant-colonel Jones) to remark, that those sieges having been undertaken and executed under circumstances and deficiencies which did not admit of regular attacks according to established rule, cannot be received as cases which afford any reason for departing from

long-established practice; and that the defence of the breaches at Badajoz, which has thrown some popular lustre on M. Carnot's work, could not have succeeded against an attack conducted, throughout, according to regular process. M. Carnot may perhaps dispute illustrations from British talent and experience, or we should have presented him with other references to facts contained in colonel Jones's excellent work, in support of other parts of our reasoning.'

PART II.

OF FIELD FORTIFICATION. Field, or temporary fortification, having the same general objects as more permanent works, only differs from them in the means that may be accessible for attacking or defending them.

Field works are thrown up, merely for a short time: often in haste, without either choice or preparation of the materials employed; with very few means at hand, and sometimes in presence, as it were, of the enemy; besides, there are many cases in which they are not intended to resist an attack supported by cannon, and, when they are, the nature of the guns which will probably be brought against them may be different, according to the importance of the works. Lastly, field-works are usually attacked by troops formed into columns; which, advancing rapidly in the direction of their capitals, threaten many points at once; therefore, the dispositions for their defence, ought to be different from those of permanent works, &c. The maxims or general rules that are to be observed in them are;

1. In general, a saliant angle should not be less than sixty degrees, especially when it is undefended by any flank fire.

2. The saliants being the most exposed points, particularly when they are not flanked, their defence ought to be carefully attended to; when the ground, and intended object of the work you construct, will allow you to direct the saliants towards some natural obstacles which prevent the enemy approaching them on the prolongation of the capitals, you ought to avail yourself of that advantage; but, if you cannot direct the saliants thus, they must be protected, if possible, by some artificial obstacles.

3. In tracing field-works, let there be as many flank defences as possible.

4. When one part of a fortification is to flank another, it must be so disposed as to make with it an angle not less than ninety degrees, and exceeding as little as possible ninety degrees; in order that the ditch and counterscarp of the part flanked, may be defended by a direct fire from that which flanks it.

5. The length of the lines of defence ought not to exceed eighty toises at most.

6. Avoid the second flank defence, unless you are obliged to have recourse to it.

7. Be careful not to suffer any cover in the vicinity of a work, under which the assailants may approach unperceived.

8. Dead angles are to be avoided as much as possible.

9. A fortification must always be proportioned to the number of men who are to defend it;

and, the length of the parapet remaining the same, you ought to enclose within it the greatest possible surface.

10. Before you begin a work, you ought to ascertain whether you have sufficient means for completing it in time.

We can only find room for a sketch of the principal or out-line of field-works.

Of redans or flêches. As redans or flêches, plate VI. fig. 3, can be quickly and easily constructed, they are frequently used in the field, where few means are at hand; besides, in many circumstances, the intended object of a work does not require that it should be able to afford an obstinate defence. Weak indeed is that which a redan can make, particularly when isolated; for then, independent of being easily carried in front, owing to the undefended sector fa g, its gorge b c is also greatly exposed, and you ought not to rely on the defence of a redan, unless it is supported in its rear; such as, for instance, redans thrown up in front of an army you intend to intrench, and on the banks of a river to cover a bridge, or defend a ford.

Sometimes redans are placed in front of a main work, either to cover its communications with the country, or to defend some parts of the ground which cannot be seen from it, and would be of advantage to the enemy in directing their attacks: or in short to procure a cross fire on the capitals of the main work, and keep the enemy at a distance from it. Redans so disposed are called lunettes.

No fixed rules can be given with regard to the length and direction of the faces of a redan, since both vary according to the ground, the intended object of the work, and the strength of the detachment that it is to cover, &c.

Of redoubts.-Redoubts, as well as redans, are frequently used in the field; where, as isolated works, they are employed, when the post or detachment to be intrenched being abandoned to its own strength, and without any protection in its rear that may prevent its being turned, it becomes necessary to enclose it entirely, so as to secure it from the attacks which the enemy may make upon it on all sides. Redoubts are extremely proper for covering an advanced post, a grand guard, or a communication; for defending a defile, a height; for protecting a retreat, the passage of a river, ford, or bridge; for supporting the wings of an army, a line of frontiers, &c.; independent of being easily constructed, they have also the advantage of affording a very good defence when supported from without, and even of being sometimes effectually used instead of fortins or field-forts, which in general require more time and materials for their construction, and a more numerous garrison for their defence.

The requisite length of the sides of a redoubt depends, not only on the extent which the parapet must have, in order that the garrison may man it properly, but on the necessary interior space for containing the men. It should also be considered, whether the troops are to reside in the work, or to remain there for a short time; as it happens, for instance, when a work is sufficiently near a main body of troops to communicate easily with them, and receive reinforce