LA SCALA DI MOMO AI MUSEI VATICANI.Curve coniche gobbe e superfici rigate da esse generate.

This study is part of a more vast research that aims to examine in depth the geometrical-spatial origin of skew curvesbelonging to conical surfaces of revolution: conical spiral and conical helix. The study begins with an investigationconcerning the geometrical tracing, and the spatial origin of both the skew curves and the ruled surfaces they generate,carrying out a comparison of the different formal characteristics through a number of algorithms that control the referenceproperties, written within the renown Rhinoceros plug-in, Grasshopper. Then follows an in-depth analysis of anadmirable example of architecture dating back to the first thirty years of the past century and made by the ArchitectEngineer Giuseppe Momo: the double-ramp helicoidal stair, located at the entrance of the Vatican Museums in Rome(1929-1932). According to project designs found in literature, and through innovative graphical analyses, thegeometrical-formal system of the work object of study is here illustrated.