Giovanni Giorgi's contribution to the rationalized System of Units, 1901-1902

The contributions collected here range from historical and technical insights into the International System of Measurement (SI), to testimonies regarding Giovanni Giorgi’s per- sonal library and its public purpose, to a presentation by the “Galileo Galilei” Technical Institute in Rome, the oldest technical institute in Italy’s capital city, which keeps alive the memory of the engineer and scientist. The picture is completed by a reflection on the relationship between mankind and measurable quantities, a theme that runs through the history of science, from natural philosophy to modern precision technologies.