10 DECEMBER 1859, Page 15

BOOKS. _

MODERN FORTLFICATION.* SIR HOWARD DOUGLAS has modestly described his book as a re- print, and in fact the basis of the first part devoted, to the science of fortification was published forty years ago. But the word re- print does not well describe a work which has been thoroughly revised, enriched with the experiences of those forty years and augmented by the addition of two important Parts—those on Intrenched Camps and National Defence. This amount of re- vision and augmentation makes the book practically a new one, and as such it should find. its way into the libraries not only of all military men, but of those of the general public, who, awakened to the dangers of the country, have taken the subject of national defence into serious consideration. In the main the essay on fortification is above the reach of the non-professional mind, but the other chapters cannot fail, if read with due respect for the high authority from whom they proceed, to produce a wholesome effect and. sounder views of national defence than have hitherto prevailed.

The first part is an exposure of the unsoundness of that system of fortification which M. Carnet, ander the eye of Napoleon, pro- pounded for the defence of the French frontiers, and which was intended. to restore the supremacy of the defence over the attack, and thus counterwork the genius of Vauban. Carnet proposed to do this by his plan of vertical fire, that is, by causing the ar- tillery of the besieged place to send a hail of small bullets into the trenches of the besiegers when they had approached the place. Sir Howard Douglas demonstrates the ineffectual, almost harmless nature of Carnet's famous showers of musket balls, and the radi- cal defects of the system of fortification he devised, as proved six-and-thirty years ago at Woolwich by actual experiment. Carnoes plan was eagerly, too eagerly, adopted by the German engineers ; and here is the remarkable fact in the history of this question. What the French engineer recommended has been ex- tensively adopted by the Austrians and Prussians, but it has not been adopted by the French. Indeed, modern French engineers have been engaged in showing how these German fortresses

may be best attacked and reduced Sir Howard Douglas minutely describes the great German fortresses, and advances sound reasons for his opinion, as strong now as it was in 1821, that they are constructed on an erroneous, insecure, and con- demned system. Speaking of Verona, which he thinks the French Emperor would have attempted to carry by main force, he says- " When these novel construction. shall be tested in a regular siege, car- ried on with the powerful aid of modern artillery, it will be found, as may be inferred from what has been described in the third chapter of this work, that the masonry defences in the ditches which are substitutes for the flanks of bastions, and reveled scarps, will be destroyed from afar, though not seen. No masonry defences can withstand the vast powers which modern artillery will bring against them in all future sieges, and earthern works only, of increased thickness, can withstand the destructive effects of such artillery. All ramparts must therefore be constructed of earth as far down as they can be seen, and the masonry defences must be formed in the rampart, so as to rise no higher than the crest of the covered way, or other outwork : thus leaving the scarp and the counter-scarp only of masonry. It appears, there- fore, that the modern artillery, far from justifying the proposed alterations in the conformation of ramparts and parapets, will render it necessary to retain the old form in the profiles of fortifications."

It may be observed that Sir Howard Douglas is opposed to the system of circular fortresses projected by Mr. James Fergusson, bat he admits that ramparts of earth have an advantage over masonry in resisting the crushing effects of the heavy artillery in use at present.

In his valuable chapter on " Intrenched Camps" Sir Howard Douglas shows how dangerous they may become when they are constructed in positions where they can be surrounded or turned. Generals who have risked their armies in intrenched camps not having those advantages, have, in every instance, been placed in imminent peril, or have been compelled to succumb. The model of the exception to the rule is an intrenched position like Torres Vedras, which could not be turned, and so the communications of the defending army with their base of operations could not be endangered. Our author likens Verona, Lintz, Ulm, and llastadt to the camp at Pirna, which Frederick the Second neutralized by blockading it, and then, after beating Brown at Lowositz, cap- tured with the army it contained. Armies in these intrenched camps may be reduced by famine, or taken by storm. Not so lines, likethose at Torres Vedras ; for these must be captured, if at all, by a front attack.

"The so-called siege of Sevastopol, adduced by Mr. Fergusson and others as the greatest and. most instructive siege that ever took place, was not a siege. It was the attack of a great intrenched Ike, whose commu- nications with its base were never interrupted. In this attack, the allied army had to contend, not only with the very strong garrison which the fortress contained, but, through it, with all the resources of Russia; just as the army before the lines of Torres Vedras may be said to have contended against all the resources of England, as they .were poured into Lisbon by sea. The most instructive lesson that can be learnt from that undertaking is, never to attempt the attack of a fortress without completely investing it, so that no succour can get in. It was entirely through the inadequacy of the allied army to effect that first condition of a siege, that the attack of Sevastopol was PA protracted and so sanguinary; and not because its de- fames consisted of earthen ramparts."

• Observations- on Modern Systems of Fortification, including that proposed by it Carnot, and a comparison of the Polygonal with the Bastion System • to which are added some reflections on intrenched Positions, and a Tract on the Naval, Lit- toral, and Internal Defence of England. By General Sir Howard Douglas, Bart. With numerous Illustrations. Published by Murray.

The principles that should guide a general in the choice of a position for an intrenched camp, and the kind of troops to be thrown into it, are concisely described.—

" Intrenched camps should combine defensive and offensive faculties : the camp may be formed in contiguity to a place, and armies may, in Cue of need, take refuge in them; yet the camp itself should be an offensive po- sition, from which the troops it contains may be always ready to take the offensive in the field. To place in such camps troops of secondary cha- racter, incapable of acting efficiently in the field, would deprive an in- trenched camp of the great object for which it should be constructed. None, therefore, but well-appointed and well-exercised troops, fit for any service in the field, should occupy intrenched camps, on strategical points."

Sir Howard Douglas insists on the necessity of keeping an array destined to defend a nation in positions whence it can resume offensive operations, and of not weakening that army by sending bodies to garrison open towns and small fortresses. Certainly in defending England, we must rely upon offensive operations and our arrangements should all be calculated with a view to offensive warfare. Even if compelled to give ground it should never be forgotten that falling back should only be effected. with the object of recruiting strength for a forward spring. Means of offence will always be the beat means of defence.

The Tract on the Defence of England is peculiarly worthy of attentive study, especially at this moment when we are organ- izing defenders. In the opinion of our author, our land forces should consist of Regulars' Militia, and Volunteers. The Militia he would raise by ballot and train, with great care, so as to enable them to act with the Line. Unlike Sir John Burgoyne, he does not despise our hedgerows ditches, farm-houses, as means of defence in the hands of volunteers ; but he does distinctly say that the regular army alone is not adequate to the preservation of our safety. He also asks for better means of flank communica- tion along the south coast, especially in Kent and Sussex, and. cites this opinion expressed by the Duke of Wellington early in

18,52, when discussing projects of defence Look at these splendid heights all along the coast," exclaimed the Duke ; "give me communications which admit of rapid flank movements along these heights, and I might set anything at defiance." Thera should also be flank communications in Essex and Suffolk.

Volunteer captains and volunteers will find excellent advice in these pages. We heartily commend the Tract to their notice, and only regret that it is not 'published. separately in a cheap and portable form for the instruction and guidance of those irregular levies of which Sir Howard Douglas so highly approves.