Krokowski and Herr Settembrini on his arrival up here. In order to learn something⁠—it had not much mattered what⁠—he had learned in his technical school about statics, about supports capable or flection, about loads, about construction as the advantageous utilization of mechanical material. It would of course be childish to think that the science of engineering, the rules of mechanics, had found application to organic nature; but just as little might one say that they had been derived from organic nature. It was simply that the mechanical laws found themselves repeated and corroborated in nature. The principle of the hollow cylinder was illustrated in the structure of the tubular bones, in such a way that the static demands were satisfied with the precise minimum of solid structure. Hans Castorp had learned that a body which is put together out of staves and bands of mechanically utilizable matter, conformably to the demands made by draught and pressure upon it, can withstand the same weight as a solid column of the same material. Thus in the development of the tubular bones, it was comprehensible that, step for step with the formation of the solid exterior, the inner parts, which were mechanically superfluous, changed to a fatty tissue, the marrow.