They were taken, not to serve as a hindrance to French heroism, but as a precaution against treacherous crime. The railway does not carry merely soldiers, ammunition and other war material against which it may be allowable to use violent measures; it also conveys a great number of wounded, doctors, hospital attendants, and other perfectly harmless persons. Is a peasant or franc-tireur to be allowed to endanger hundreds of those lives by removing a rail or laying a stone upon the line? Let the French see that the security of the railway trains is no longer threatened and the journeys made by those hostages will be merely outings, or our people may even be able to forgo such precautionary measures.
In the South African War, Field-Marshal Earl Roberts issued at Pretoria, on June 19, 1900, a proclamation one section of which authorised the placing of leading men among the Boers on the locomotives of the trains run by the British on the occupied territory; but this particular section was withdrawn eight days afterwards.
The English view of the practice in question is thus defined in the official "Manual of Military Law" (Chap. XIV, "The Laws and Usages of War," par. 463):—
Such measures expose the lives of inhabitants, not only to the illegitimate acts of train wrecking by private enemy individuals, but also to the lawful operations of raiding parties of the armed forces of the belligerent, and cannot, therefore, be considered a commendable practice.
To guard against the attacks made on the railway lines in the Orange Free State and the Transvaal during the British occupation, entrenched posts were placed at every bridge exceeding a 30-feet span; constant patrolling was maintained between these posts; and the block-houses introduced (in 1901) by Lord Kitchener were erected along all the railway lines, at distances of about 2,000 yards. Each block-house, also, was garrisoned by about ten men, and each was surrounded by wire entanglements which, together with various kinds of alarm fences, were also placed between the block-houses themselves in order both to impede the approach of the enemy and to warn the garrison thereof.
Block-houses are to-day regarded as one of the chief means of protecting railways against attacks. Their construction and equipment are dealt with by Major W. D. Connor, of the Corps of Engineers, U.S.A., in "Military Railways" (Professional Papers, No. 32, Corps of Engineers, U.S. Army, Washington, 1910).
Supplementary to the adoption of this block-house system, in time of war, is the practice followed in various Continental countries, in time of peace, of building permanent fortresses, in solid masonry, alongside railway bridges crossing important rivers. In some instances the fortress is so constructed that the railway lines pass through the centre of it. Not only, as a rule, are these fortresses extremely solid and substantial, but they may be provided with bomb-proof covers and be stocked with a sufficient supply of provisions to be able to stand, if necessary, a fairly prolonged siege. One can assume, also, that the garrison would have under its control facilities arranged in advance for the destruction of the bridge, as a last resort, in case of need.
The theory is that such fortresses and their garrisons should be of especial advantage, on the outbreak of war, in checking any sudden invasion and allowing time for the completion of defensive measures. Their construction in connection with all the principal railway bridges crossing the Rhine was especially favoured in Prussia after the war of 1870-1.