The armament of the forts would consist of a hundred and sixty guns of large calibre, and that of the batteries of forty-five guns of long range. With the reserve park this would give a total of two hundred and thirty pieces of ordnance.
Harnessed guns would be also necessary to support the trenches of the passive defence.
| Each fort would cost about £48,900. The eight together | £391,200 |
| Each battery or redoubt would cost about £6,000. The thirteen together | 78,000 |
| ———— | |
| Total | £469,200 |
| ======== |
To make head against an invasion at all points at once has always been a difficult problem to solve; and it is still more so if we confine ourselves to the defensive, for the enemy starts from a base of operation with a view to concentrating himself upon a point unknown to the defenders. The latter has therefore only a line to oppose to the apex of a triangle of action. He must limit himself to preserving the heart of the country and certain districts that are already naturally protected, and which allow him to operate on the flanks of the invading forces; regions behind which lie extensive tracts of country from which supplies may be drawn.
Let us suppose that on the zone of defence of which La Roche-Pont forms the centre, an army of a hundred and fifty thousand men were assembled, which was able to reach Belfort through Besançon or by the road from Vesoul to Langres through Gray or Châtillon-sur-Seine through Dijon, these towns of Besançon, Vesoul, Langres, and Dijon being themselves in a condition to arrest the enemy's advance: the latter in attempting to make his way to Paris would be obliged either to watch this zone with an army of three hundred thousand men, or to move, and that with extreme caution, along the Lunéville and Nancy routes.
If a defensive zone of the same importance is disposed on the north, a point becomes very dangerous, especially if the capital is provided with an enceinte de préservation, and an enceinte de combat allowing an army to manœuvre.
Three hundred thousand men therefore would be required to watch the defensive zone of Burgundy and the same number that of the north, and four hundred thousand men to invest Paris; total, one million, without reckoning the troops required for keeping open the communication between the three armies and guarding the base of operations.
It follows that the slightest check might entail a serious disaster.
As the army of Metz under the ramparts of the town was not able to manœuvre, the two hundred thousand men employed in blockading it were rendered inactive for two months.
If the French army had been able to move within a perimeter of 60 miles, with a good supply of provisions, it would have reduced three hundred thousand men to inaction; since the Germans, who leave nothing to chance, reckon—and not unreasonably—that on the field it is desirable to be at least two to one. It would seem then that the art of war now-a-days—as far as resistance to an invader is concerned—consists not in endeavouring to defend any extensive lines which may be taken or outflanked, but in establishing a small number of centres of defence, sufficiently remote from each other and connected by a system of railways in the rear; which are capable of holding out long, and which compel the enemy either to divide in order to watch them or to take them, or to expose his flanks to an attack if he leaves them alone, or to see himself cut off from his base of operations if he advances en masse against one of them without covering himself against the others....