Gray, dear friend, is all theory, and green is the golden tree of life. When one sees the railway superstructure in its current form, with rails laid on cross ties embedded in gravel, everything appears so simple and obvious that one might think that creating a superstructure is a straightforward craft and that even the description of this purely craft-based work would soon be dismissed. A comparison with a locomotive, which is closely related to the superstructure because it must work in conjunction with it, with its many individual parts and its complex construction - just think of an electric locomotive - or with a powerful, wide-spanning bridge that serves as a "support" forming a counterpart to the rail, seems to particularly highlight the subordinate significance of the railway superstructure. That for the design of a locomotive or such.