Similar fortresses, or "interrupting forts," as the Germans call them, are also built for the protection of important tunnels, junctions, locomotive and carriage works, etc.
Another method adopted for the safeguarding of railway lines in war is the use of armoured trains; though in practice these are also employed for the purposes of independent attacks on the enemy, apart altogether from any question of ensuring the safety of rail communication.[10]
For the protection of locomotives and rolling stock, and to prevent not only their capture but their use by the enemy, the most efficacious method to adopt is, of course, that of removing them to some locality where the enemy is not likely to come.
When, in 1866, Austria saw that she could not hold back the Prussian invader, she took off into Hungary no fewer than 1,000 locomotives and 16,000 wagons from the railways in Bohemia and Saxony. Similar tactics were adopted by the Boers as against ourselves in the war in South Africa. On the British troops crossing into the Orange Free State, from Cape Colony, they found that the retreating enemy had withdrawn all their rolling stock, as well as all their staffs from the railway stations, leaving behind only a more or less damaged line of railway. Subsequently, when the forces occupied Pretoria, they certainly did find there sixteen locomotives and 400 trucks; but the station books showed that in the previous forty-eight hours no fewer than seventy trains, many of them drawn by two engines, had been sent east in the direction of Delagoa Bay.
When it is not practicable to withdraw locomotives and rolling stock which it is desired the enemy shall not be able to use, the obvious alternative is that measures should be taken either to remove vital parts or to ensure their destruction. Certain of the methods adopted during the Civil War in America were especially efficacious in attaining the latter result. In some instances trains were started running and then—driver and fireman leaping off the engine—were left to go into a river, or to fall through a broken viaduct. In other instances two trains, after having had a good supply of explosives put in them, would be allowed to dash into one another at full speed. Many locomotives had their boilers burst, and wagons were set on fire after having been filled up with combustibles.
Still another method which has been adopted with a view to preventing an enemy from using the railways he might succeed in capturing is that of constructing them with a different gauge. The standard gauge of the main-line railways in France, Germany, Holland, Belgium, Denmark, Austria-Hungary, Italy, Switzerland, Roumania and Turkey (like that, also, of railways in Great Britain, Canada and the United States), is 4ft. 8½in., allowing trains to pass readily from one country to the other with the same rolling stock; but the gauge of the Russian railways is 5ft., necessitating a transshipment from one train to another when the frontier is reached. Similar conditions are found in Spain and Portugal, where the standard gauge is 5ft. 6in.[11]
Russia adopted her broader gauge so that, in case of invasion, the invader should not be able to run his rolling-stock over her lines, as Germany, for instance, would be able to do in the case of the railways of Belgium and France. Thus far, therefore, Russia strengthened her position from the point of view of defence; but she weakened it as regards attack, since if she should herself want, either to become the invader or to send troop trains over neighbouring territory to some point beyond, she would be at a disadvantage. In the Russo-Turkish War of 1877-78, when the Russian forces passed through Roumania on their way to Turkey, the difference in gauge between the Russian and the Roumanian railways caused great delay and inconvenience by reason of the necessary transfer of troops, stores, guns, ammunition, torpedo boats, etc., at the frontier.
It should, also, be remembered that the reduction of a broad gauge to a narrow one is a much simpler matter, from an engineering point of view, than the widening of a narrower gauge into a broad one. In the former case the existing sleepers, bridges, tunnels, platforms, etc., would still serve their purpose. In the latter case fresh sleepers might have to be laid, bridges and tunnels widened or enlarged, and platforms and stations altered, use of the broader-gauge rolling stock thus involving an almost complete reconstruction of the railway lines. To this extent, therefore, the balance of advantage would seem to be against the country having the broader gauge. The conclusion may, at least, be formed that such a country is far more bent on protecting her own territory than on invading that of her neighbours.