In the proposals which Pönitz himself advanced for providing Germany with a complete network of strategical lines he sought to combine, as far as possible, the commercial and the military principle; though the subsequent predominance, in most countries, of the economic element in regard to railways in general strengthened the force of his contention that an ideal system was not necessarily a practicable one. The suggested geometrical design was, nevertheless, not lost sight of, and it continued to be regarded as the plan that should, at least, be followed in respect to strategical railways, as far as circumstances would permit. Dealing with this particular subject in his "Geschichte und System der Eisenbahnbenutzung im Kriege" (Leipzig, 1896), Dr. Josef Joesten included the following among the conditions which, theoretically and practically, should enable a railway system to respond to the necessities of war:-- 1. To each of the strategical fronts of the national territory there should be the largest possible number of railway lines, all independent the one of the other. 2. The converging lines terminating at the bases of concentration, and more especially those leading to the coast or to great navigable rivers, should be crossed by numerous transverse lines in order to allow of the rapid passing of troops from any one of the lines of concentration to any other. 3. Positions or localities having a recognised strategical value should be selected as the places where the two types of lines should cross, and these intersection points, when they are near to the frontier, should themselves be protected by fortifications serving as _points d'appui_ for movements of advance or retirement. It is possible that, if the building of railways in Germany had been left entirely to the State from the outset, these principles would have been generally followed there; but in Prussia the private lines taken over as the result of the policy of nationalisation adopted by that country--the total length of those acquired since 1872 being now nearly 10,000 miles--had been originally constructed to serve, not strategic, but economic purposes, and, more especially, the industrial interests of Westphalia and the Rhineland, the Government having been left by private enterprise to provide, not alone the strategical lines, but, also, the lines that were wanted to serve the less promising economic requirements, of Eastern Prussia. To say, therefore, as some writers have done, that the Prussian--if not the German--railways as a whole have been designed to serve military purposes is erroneous. It is none the less true that the adoption of the principle of State ownership conferred alike on Prussia and on other German States a great advantage in enabling them both to build strategical lines as, ostensibly, part of the ordinary railway system and to adapt existing lines to military purposes so far as conditions allowed and occasion might require.