A more accurate idea of the real bearings of German railways on the military and strategical situation can be gathered from the large map ("Kartenbeilage I") which accompanies the "Bericht" presented to the Kaiser, in 1911, by the Prussian Minister of Public Works under the title of "Die Verwaltung der öffentlichen Arbeiten in Preussen, 1900 bis 1910." On this map a clear distinction is drawn between State-owned and company-owned lines, while difference in colouring shows the additions made to the State system during the decade either by construction of new lines or by State acquisition of existing lines.
One especially noticeable feature brought out by this map is the fact that, in addition to the innumerable railway lines built either to the frontiers or establishing intercommunication and exchange of traffic between those lines themselves, there is an almost unbroken series running parallel to the coasts of Pomerania and East Prussia, and thence southward all along and close to the frontiers of Russia and Russian Poland. In this way troops can be moved, not only by different routes to many points along the Baltic coast or the Russian frontier, but, also, from one of these coastal or frontier points direct to another, as may be desired.
The strategical significance of this arrangement is sufficiently obvious; but any possible doubt as to the purpose aimed at is removed by some observations thereon made by Joesten, who further says in his "Geschichte und System der Eisenbahnbenutzung im Kriege":—
If it is true that, generally speaking, the best railways for general purposes constitute excellent lines of communication for armies, it is no less true that good, or very good, strategical lines cannot, and ought not to, in all cases constitute good commercial lines. In support of this assertion one can refer to the immense extent of railway lines on the coasts of Pomerania. These lines, which are of the first importance from a strategical point of view, have only a moderate value from a commercial standpoint, considering that they do not connect the interior of the country with any district providing goods or passenger traffic on a material scale, and only provide means of communication between localities having identical needs.
What is thus admitted in regard to the coastal railways of Pomerania applies no less to many, if not to most, of the frontier lines in East Prussia, West Prussia and Silesia.
Not only, again, is the number of German lines going to the frontiers, and no farther, out of all proportion to the number of those providing for international communication, but the map on which these observations are based shows that between 1900 and 1910 there were added to the Prussian State system many lines which (1) established additional transverse links between those already going to the Russian frontier, (2) provided alternative routes thereto, or (3) supplemented the lines which skirt the frontier, a few miles inland, by branches going therefrom to strategic points actually on the frontier itself.
As against this construction of an elaborate network of strategical lines towards and along the Russian frontier, there must be put the fact that although, by this means, Germany acquired the power to effect a great and speedy concentration of troops on the frontier itself, her locomotives and rolling stock would not be able to cross into Russia and run on the railways there because of the difference in gauge. On the eastern frontier the question as to how an invasion in large force could be effected was, consequently, quite different from that which would present itself on the western frontiers, where the railway gauges of Belgium, Luxemburg and France were the same as those of Germany.
It was certain that whenever, in the event of war, German troops were able to enter Russian territory, Russia would withdraw into the interior or else destroy such of her locomotives and rolling stock as the enemy might otherwise utilise for his own purpose. If, therefore, the Germans wanted to use the existing Russian lines, they would either have to build, in advance, locomotives and rolling stock capable of running thereon, or they would have to convert the Russian gauge of 5 feet to the German gauge of 4 feet 8½ inches, so that German trains could run on the other side of the frontier. As already remarked on page [61], the reduction of the broader gauge into a narrower one would involve fewer engineering difficulties than an expansion of the German gauge into the Russian gauge; yet even the former procedure, if carried out over any considerable length of line, would take up a good deal of time, and this would be still more the case if the Russians, when they retreated, destroyed the railway track and bridges behind them, as they might confidently be expected to do.
Dependence, again, on the existing lines across the frontier would, apart from questions of conversion and reconstruction, still give Germany only a very small number of railway routes into Russia, and these, also, at points where the opposition offered might be especially active.
What, in these circumstances, Germany evidently planned to do as soon as her troops crossed the frontier, in the event of a war with Russia, was to supplement the strategical lines on her own side of that frontier by military light railways which, laid on the ordinary roads, or on clearances to be effected, on Russian territory, would render her independent of the ordinary railways there, while offering the further advantage (1) that the laying of these narrow-gauge military lines—in rough and ready fashion, yet in a way that would answer the purposes of the moment—could be effected in shorter time than the gauge-conversion and the reconstruction of the Russian trunk lines would take; and (2) that these military railways could be built from any points along the frontier which were capable of being reached direct from the German strategical lines, and offered either an existing road or the opportunity of making one for the purpose.