Ferro-Concrete Ship,
constructed but never built.

Proposition to build a Steam-train ferry for use between Sweden and England was laid 1921 but it dident came longer then to a proposition, beacuse no company or yard was interested to put money in this adventure. Below is a generelarrangement from a Swedish technical paper from 1921.
The underbody was to be made of Ferro-Concrete and the superstructure of steele.