In her relations with _France_, Germany's efforts to improve still further her rail communications to the eastern and north-eastern frontiers of that country have been continuous since the war of 1870-1, on which campaign she started with a great advantage over the French since she was able to concentrate her troops on those frontiers by nine different routes, namely, six in North Germany, and three in South Germany, whereas France herself had then only three available. The course adopted by Germany has been (1) to secure a larger number of routes to the French frontier, South Germany's three lines, for instance, being increased to six; (2) to provide double track, or to substitute double for single track, for lines leading to the frontier and having a strategical importance; (3) to construct lines which cross transversely those proceeding direct to the French frontiers, thus allowing of intercommunication and transfer of traffic from one to another; and (4) improvement of the interior network of lines, with a view to facilitating military transport services in time of war. "Altogether," says Joesten, "we have nineteen points at which our railways cross the Rhine, and sixteen double-track lines for the transport of our troops from east to west, as against the nine which were alone available for concentration in 1870." While showing all this activity on the immediate frontiers of France, Germany was no less zealous in providing alternative routes for a fresh invasion of French territory, the adoption of this further policy being obviously inspired by the energy that France was herself showing in the strengthening of her north-east frontier against invasion. One such alternative route was represented by _Luxemburg_. Not only did Germany have lines of her own on the north, south, and east of Luxemburg, but the lines within the Grand Duchy itself had passed under German control; and if Germany thought fit to disregard her treaty obligations, and use the lines for strategical purposes, Luxemburg was powerless to prevent her from so doing. Another alternative route was by way of _Belgium_; and the various developments of Germany's railway policy on the Belgian frontier since 1908 point in an unmistakable manner to deliberate preparation on her part for an invasion of that country, whether for the purpose of passing through it, as a means of reaching a more vulnerable part of French territory than the strongly fortified north-east corner, or in pursuance of designs against Belgium itself. The full story of Germany's activity in this direction will be found in a series of articles from the _Fortnightly Review_ reproduced by the author, Mr. Demetrius C. Boulger, in "England's Arch-Enemy: A Collection of Essays forming an Indictment of German Policy during the last sixteen years" (London, 1914).[53]